80 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| // Copyright (C) 2005-2017 Andes Technology Corporation
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| 
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| #include <linux/export.h>
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| #include <linux/highmem.h>
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| #include <linux/sched.h>
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| #include <linux/smp.h>
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| #include <linux/interrupt.h>
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| #include <linux/bootmem.h>
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| #include <asm/fixmap.h>
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| #include <asm/tlbflush.h>
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| 
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| void *kmap(struct page *page)
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| {
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| 	unsigned long vaddr;
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| 	might_sleep();
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| 	if (!PageHighMem(page))
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| 		return page_address(page);
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| 	vaddr = (unsigned long)kmap_high(page);
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| 	return (void *)vaddr;
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| }
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| 
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| EXPORT_SYMBOL(kmap);
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| 
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| void kunmap(struct page *page)
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| {
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| 	BUG_ON(in_interrupt());
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| 	if (!PageHighMem(page))
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| 		return;
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| 	kunmap_high(page);
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| }
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| 
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| EXPORT_SYMBOL(kunmap);
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| 
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| void *kmap_atomic(struct page *page)
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| {
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| 	unsigned int idx;
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| 	unsigned long vaddr, pte;
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| 	int type;
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| 	pte_t *ptep;
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| 
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| 	preempt_disable();
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| 	pagefault_disable();
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| 	if (!PageHighMem(page))
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| 		return page_address(page);
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| 
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| 	type = kmap_atomic_idx_push();
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| 
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| 	idx = type + KM_TYPE_NR * smp_processor_id();
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| 	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
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| 	pte = (page_to_pfn(page) << PAGE_SHIFT) | (PAGE_KERNEL);
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| 	ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
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| 	set_pte(ptep, pte);
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| 
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| 	__nds32__tlbop_inv(vaddr);
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| 	__nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
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| 	__nds32__tlbop_rwr(pte);
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| 	__nds32__isb();
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| 	return (void *)vaddr;
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| }
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| 
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| EXPORT_SYMBOL(kmap_atomic);
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| 
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| void __kunmap_atomic(void *kvaddr)
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| {
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| 	if (kvaddr >= (void *)FIXADDR_START) {
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| 		unsigned long vaddr = (unsigned long)kvaddr;
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| 		pte_t *ptep;
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| 		kmap_atomic_idx_pop();
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| 		__nds32__tlbop_inv(vaddr);
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| 		__nds32__isb();
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| 		ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
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| 		set_pte(ptep, 0);
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| 	}
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| 	pagefault_enable();
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| 	preempt_enable();
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| }
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| 
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| EXPORT_SYMBOL(__kunmap_atomic);
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