65 lines
1.4 KiB
C
65 lines
1.4 KiB
C
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/*
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* arch/sh/mm/kmap.c
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*
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* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
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* Copyright (C) 2002 - 2009 Paul Mundt
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*
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* Released under the terms of the GNU GPL v2.0.
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*/
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/fs.h>
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#include <linux/highmem.h>
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#include <linux/module.h>
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#include <asm/mmu_context.h>
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#include <asm/cacheflush.h>
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#define kmap_get_fixmap_pte(vaddr) \
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pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
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static pte_t *kmap_coherent_pte;
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void __init kmap_coherent_init(void)
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{
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unsigned long vaddr;
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if (!boot_cpu_data.dcache.n_aliases)
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return;
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/* cache the first coherent kmap pte */
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vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
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kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
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}
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void *kmap_coherent(struct page *page, unsigned long addr)
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{
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enum fixed_addresses idx;
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unsigned long vaddr, flags;
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pte_t pte;
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BUG_ON(test_bit(PG_dcache_dirty, &page->flags));
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inc_preempt_count();
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idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;
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vaddr = __fix_to_virt(FIX_CMAP_END - idx);
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pte = mk_pte(page, PAGE_KERNEL);
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local_irq_save(flags);
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flush_tlb_one(get_asid(), vaddr);
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local_irq_restore(flags);
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update_mmu_cache(NULL, vaddr, pte);
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set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
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return (void *)vaddr;
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}
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void kunmap_coherent(void)
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{
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dec_preempt_count();
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preempt_check_resched();
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}
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