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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#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/memblock.h>
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#include <asm/fixmap.h>
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#include <asm/tlbflush.h>
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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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EXPORT_SYMBOL(kmap);
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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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EXPORT_SYMBOL(kunmap);
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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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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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type = kmap_atomic_idx_push();
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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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__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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EXPORT_SYMBOL(kmap_atomic);
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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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EXPORT_SYMBOL(__kunmap_atomic);
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