mirror of https://gitee.com/openkylin/linux.git
42 lines
875 B
C
42 lines
875 B
C
/* highmem.c: arch-specific highmem stuff
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*
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* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/highmem.h>
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#include <linux/module.h>
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void *kmap(struct page *page)
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{
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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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return kmap_high(page);
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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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if (in_interrupt())
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BUG();
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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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struct page *kmap_atomic_to_page(void *ptr)
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{
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return virt_to_page(ptr);
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}
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EXPORT_SYMBOL(kmap_atomic_to_page);
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