321 lines
		
	
	
		
			7.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			321 lines
		
	
	
		
			7.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef __M68K_MMU_CONTEXT_H
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| #define __M68K_MMU_CONTEXT_H
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| 
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| #include <asm-generic/mm_hooks.h>
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| #include <linux/mm_types.h>
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| 
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| #ifdef CONFIG_MMU
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| 
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| #if defined(CONFIG_COLDFIRE)
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| 
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| #include <asm/atomic.h>
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| #include <asm/bitops.h>
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| #include <asm/mcfmmu.h>
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| #include <asm/mmu.h>
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| 
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| #define NO_CONTEXT		256
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| #define LAST_CONTEXT		255
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| #define FIRST_CONTEXT		1
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| 
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| extern unsigned long context_map[];
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| extern mm_context_t next_mmu_context;
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| 
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| extern atomic_t nr_free_contexts;
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| extern struct mm_struct *context_mm[LAST_CONTEXT+1];
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| extern void steal_context(void);
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| 
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| static inline void get_mmu_context(struct mm_struct *mm)
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| {
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| 	mm_context_t ctx;
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| 
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| 	if (mm->context != NO_CONTEXT)
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| 		return;
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| 	while (arch_atomic_dec_and_test_lt(&nr_free_contexts)) {
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| 		atomic_inc(&nr_free_contexts);
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| 		steal_context();
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| 	}
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| 	ctx = next_mmu_context;
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| 	while (test_and_set_bit(ctx, context_map)) {
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| 		ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx);
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| 		if (ctx > LAST_CONTEXT)
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| 			ctx = 0;
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| 	}
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| 	next_mmu_context = (ctx + 1) & LAST_CONTEXT;
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| 	mm->context = ctx;
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| 	context_mm[ctx] = mm;
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| }
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| 
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| /*
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|  * Set up the context for a new address space.
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|  */
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| #define init_new_context(tsk, mm)	(((mm)->context = NO_CONTEXT), 0)
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| 
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| /*
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|  * We're finished using the context for an address space.
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|  */
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| #define destroy_context destroy_context
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| static inline void destroy_context(struct mm_struct *mm)
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| {
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| 	if (mm->context != NO_CONTEXT) {
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| 		clear_bit(mm->context, context_map);
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| 		mm->context = NO_CONTEXT;
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| 		atomic_inc(&nr_free_contexts);
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| 	}
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| }
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| 
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| static inline void set_context(mm_context_t context, pgd_t *pgd)
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| {
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| 	__asm__ __volatile__ ("movec %0,%%asid" : : "d" (context));
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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,
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| 	struct task_struct *tsk)
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| {
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| 	get_mmu_context(tsk->mm);
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| 	set_context(tsk->mm->context, next->pgd);
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| }
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| 
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| /*
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|  * After we have set current->mm to a new value, this activates
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|  * the context for the new mm so we see the new mappings.
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|  */
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| #define activate_mm activate_mm
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| static inline void activate_mm(struct mm_struct *active_mm,
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| 	struct mm_struct *mm)
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| {
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| 	get_mmu_context(mm);
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| 	set_context(mm->context, mm->pgd);
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| }
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| 
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| #define prepare_arch_switch(next) load_ksp_mmu(next)
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| 
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| static inline void load_ksp_mmu(struct task_struct *task)
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| {
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| 	unsigned long flags;
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| 	struct mm_struct *mm;
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| 	int asid;
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| 	pgd_t *pgd;
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| 	p4d_t *p4d;
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| 	pud_t *pud;
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| 	pmd_t *pmd;
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| 	pte_t *pte;
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| 	unsigned long mmuar;
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| 
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| 	local_irq_save(flags);
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| 	mmuar = task->thread.ksp;
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| 
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| 	/* Search for a valid TLB entry, if one is found, don't remap */
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| 	mmu_write(MMUAR, mmuar);
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| 	mmu_write(MMUOR, MMUOR_STLB | MMUOR_ADR);
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| 	if (mmu_read(MMUSR) & MMUSR_HIT)
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| 		goto end;
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| 
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| 	if (mmuar >= PAGE_OFFSET) {
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| 		mm = &init_mm;
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| 	} else {
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| 		pr_info("load_ksp_mmu: non-kernel mm found: 0x%p\n", task->mm);
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| 		mm = task->mm;
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| 	}
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| 
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| 	if (!mm)
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| 		goto bug;
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| 
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| 	pgd = pgd_offset(mm, mmuar);
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| 	if (pgd_none(*pgd))
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| 		goto bug;
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| 
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| 	p4d = p4d_offset(pgd, mmuar);
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| 	if (p4d_none(*p4d))
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| 		goto bug;
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| 
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| 	pud = pud_offset(p4d, mmuar);
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| 	if (pud_none(*pud))
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| 		goto bug;
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| 
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| 	pmd = pmd_offset(pud, mmuar);
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| 	if (pmd_none(*pmd))
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| 		goto bug;
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| 
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| 	pte = (mmuar >= PAGE_OFFSET) ? pte_offset_kernel(pmd, mmuar)
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| 				     : pte_offset_map(pmd, mmuar);
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| 	if (pte_none(*pte) || !pte_present(*pte))
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| 		goto bug;
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| 
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| 	set_pte(pte, pte_mkyoung(*pte));
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| 	asid = mm->context & 0xff;
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| 	if (!pte_dirty(*pte) && mmuar <= PAGE_OFFSET)
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| 		set_pte(pte, pte_wrprotect(*pte));
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| 
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| 	mmu_write(MMUTR, (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) |
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| 		(((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK)
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| 		>> CF_PAGE_MMUTR_SHIFT) | MMUTR_V);
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| 
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| 	mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) |
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| 		((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X);
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| 
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| 	mmu_write(MMUOR, MMUOR_ACC | MMUOR_UAA);
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| 
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| 	goto end;
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| 
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| bug:
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| 	pr_info("ksp load failed: mm=0x%p ksp=0x08%lx\n", mm, mmuar);
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| end:
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| 	local_irq_restore(flags);
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| }
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| 
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| #elif defined(CONFIG_SUN3)
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| #include <asm/sun3mmu.h>
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| #include <linux/sched.h>
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| 
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| extern unsigned long get_free_context(struct mm_struct *mm);
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| extern void clear_context(unsigned long context);
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| 
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| /* set the context for a new task to unmapped */
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| #define init_new_context init_new_context
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| static inline int init_new_context(struct task_struct *tsk,
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| 				   struct mm_struct *mm)
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| {
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| 	mm->context = SUN3_INVALID_CONTEXT;
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| 	return 0;
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| }
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| 
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| /* find the context given to this process, and if it hasn't already
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|    got one, go get one for it. */
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| static inline void get_mmu_context(struct mm_struct *mm)
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| {
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| 	if (mm->context == SUN3_INVALID_CONTEXT)
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| 		mm->context = get_free_context(mm);
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| }
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| 
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| /* flush context if allocated... */
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| #define destroy_context destroy_context
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| static inline void destroy_context(struct mm_struct *mm)
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| {
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| 	if (mm->context != SUN3_INVALID_CONTEXT)
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| 		clear_context(mm->context);
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| }
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| 
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| static inline void activate_context(struct mm_struct *mm)
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| {
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| 	get_mmu_context(mm);
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| 	sun3_put_context(mm->context);
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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,
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| 			     struct task_struct *tsk)
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| {
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| 	activate_context(tsk->mm);
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| }
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| 
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| #define activate_mm activate_mm
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| static inline void activate_mm(struct mm_struct *prev_mm,
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| 			       struct mm_struct *next_mm)
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| {
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| 	activate_context(next_mm);
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| }
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| 
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| #else
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| 
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| #include <asm/setup.h>
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| #include <asm/page.h>
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| #include <asm/cacheflush.h>
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| 
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| #define init_new_context init_new_context
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| static inline int init_new_context(struct task_struct *tsk,
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| 				   struct mm_struct *mm)
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| {
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| 	mm->context = virt_to_phys(mm->pgd);
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| 	return 0;
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| }
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| 
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| static inline void switch_mm_0230(struct mm_struct *mm)
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| {
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| 	unsigned long crp[2] = {
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| 		0x80000000 | _PAGE_TABLE, mm->context
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| 	};
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| 	unsigned long tmp;
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| 
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| 	asm volatile (".chip 68030");
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| 
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| 	/* flush MC68030/MC68020 caches (they are virtually addressed) */
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| 	asm volatile (
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| 		"movec %%cacr,%0;"
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| 		"orw %1,%0; "
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| 		"movec %0,%%cacr"
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| 		: "=d" (tmp) : "di" (FLUSH_I_AND_D));
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| 
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| 	/* Switch the root pointer. For a 030-only kernel,
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| 	 * avoid flushing the whole ATC, we only need to
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| 	 * flush the user entries. The 68851 does this by
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| 	 * itself. Avoid a runtime check here.
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| 	 */
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| 	asm volatile (
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| #ifdef CPU_M68030_ONLY
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| 		"pmovefd %0,%%crp; "
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| 		"pflush #0,#4"
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| #else
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| 		"pmove %0,%%crp"
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| #endif
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| 		: : "m" (crp[0]));
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| 
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| 	asm volatile (".chip 68k");
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| }
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| 
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| static inline void switch_mm_0460(struct mm_struct *mm)
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| {
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| 	asm volatile (".chip 68040");
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| 
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| 	/* flush address translation cache (user entries) */
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| 	asm volatile ("pflushan");
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| 
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| 	/* switch the root pointer */
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| 	asm volatile ("movec %0,%%urp" : : "r" (mm->context));
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| 
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| 	if (CPU_IS_060) {
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| 		unsigned long tmp;
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| 
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| 		/* clear user entries in the branch cache */
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| 		asm volatile (
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| 			"movec %%cacr,%0; "
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| 		        "orl %1,%0; "
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| 		        "movec %0,%%cacr"
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| 			: "=d" (tmp): "di" (0x00200000));
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| 	}
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| 
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| 	asm volatile (".chip 68k");
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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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| 	if (prev != next) {
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| 		if (CPU_IS_020_OR_030)
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| 			switch_mm_0230(next);
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| 		else
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| 			switch_mm_0460(next);
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| 	}
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| }
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| 
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| #define activate_mm activate_mm
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| static inline void activate_mm(struct mm_struct *prev_mm,
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| 			       struct mm_struct *next_mm)
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| {
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| 	next_mm->context = virt_to_phys(next_mm->pgd);
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| 
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| 	if (CPU_IS_020_OR_030)
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| 		switch_mm_0230(next_mm);
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| 	else
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| 		switch_mm_0460(next_mm);
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| }
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| 
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| #endif
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| 
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| #include <asm-generic/mmu_context.h>
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| 
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| #else /* !CONFIG_MMU */
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| 
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| #include <asm-generic/nommu_context.h>
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| 
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| #endif /* CONFIG_MMU */
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| #endif /* __M68K_MMU_CONTEXT_H */
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