cregit-Linux how code gets into the kernel

Release 4.9 arch/arm/mm/highmem.c

Directory: arch/arm/mm
/*
 * arch/arm/mm/highmem.c -- ARM highmem support
 *
 * Author:      Nicolas Pitre
 * Created:     september 8, 2008
 * Copyright:   Marvell Semiconductors Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/highmem.h>
#include <linux/interrupt.h>
#include <asm/fixmap.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include "mm.h"




static inline void set_fixmap_pte(int idx, pte_t pte)
{
	unsigned long vaddr = __fix_to_virt(idx);
	pte_t *ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);

	set_pte_ext(ptep, pte, 0);
	local_flush_tlb_kernel_page(vaddr);
}


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liu hualiu hua3570.00%150.00%


rob herringrob herring1530.00%150.00%


Total50100.00%2100.00%






static inline pte_t get_fixmap_pte(unsigned long vaddr)
{
	pte_t *ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);

	return *ptep;
}


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liu hualiu hua1965.52%150.00%


rob herringrob herring1034.48%150.00%


Total29100.00%2100.00%






void *kmap(struct page *page)
{
	might_sleep();
	if (!PageHighMem(page))
		return page_address(page);
	return kmap_high(page);
}

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nicolas pitrenicolas pitre34100.00%1100.00%


Total34100.00%1100.00%




EXPORT_SYMBOL(kmap);




void kunmap(struct page *page)
{
	BUG_ON(in_interrupt());
	if (!PageHighMem(page))
		return;
	kunmap_high(page);
}

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nicolas pitrenicolas pitre30100.00%1100.00%


Total30100.00%1100.00%




EXPORT_SYMBOL(kunmap);




void *kmap_atomic(struct page *page)
{
	unsigned int idx;
	unsigned long vaddr;
	void *kmap;
	int type;

	preempt_disable();
	pagefault_disable();
	if (!PageHighMem(page))
		return page_address(page);

#ifdef CONFIG_DEBUG_HIGHMEM
	/*
         * There is no cache coherency issue when non VIVT, so force the
         * dedicated kmap usage for better debugging purposes in that case.
         */
	if (!cache_is_vivt())
		kmap = NULL;
	else
#endif
		kmap = kmap_high_get(page);
	if (kmap)
		return kmap;

	type = kmap_atomic_idx_push();

	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
	vaddr = __fix_to_virt(idx);
#ifdef CONFIG_DEBUG_HIGHMEM
	/*
         * With debugging enabled, kunmap_atomic forces that entry to 0.
         * Make sure it was indeed properly unmapped.
         */
	BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
#endif
	/*
         * When debugging is off, kunmap_atomic leaves the previous mapping
         * in place, so the contained TLB flush ensures the TLB is updated
         * with the new mapping.
         */
	set_fixmap_pte(idx, mk_pte(page, kmap_prot));

	return (void *)vaddr;
}

Contributors
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nicolas pitrenicolas pitre11784.78%330.00%


peter zijlstrapeter zijlstra85.80%110.00%


rob herringrob herring42.90%110.00%


david hildenbranddavid hildenbrand32.17%110.00%


liu hualiu hua21.45%110.00%


stefan agnerstefan agner21.45%110.00%


russell kingrussell king10.72%110.00%


americo wangamerico wang10.72%110.00%


Total138100.00%10100.00%




EXPORT_SYMBOL(kmap_atomic);




void __kunmap_atomic(void *kvaddr)
{
	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
	int idx, type;

	if (kvaddr >= (void *)FIXADDR_START) {
		type = kmap_atomic_idx();
		idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();

		if (cache_is_vivt())
			__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
#ifdef CONFIG_DEBUG_HIGHMEM
		BUG_ON(vaddr != __fix_to_virt(idx));
		set_fixmap_pte(idx, __pte(0));
#else
		(void) idx;  /* to kill a warning */
#endif
		kmap_atomic_idx_pop();
	} else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
		/* this address was obtained through kmap_high_get() */
		kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
	}
	pagefault_enable();
	preempt_enable();
}

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nicolas pitrenicolas pitre11780.14%333.33%


peter zijlstrapeter zijlstra1913.01%222.22%


russell kingrussell king32.05%111.11%


david hildenbranddavid hildenbrand32.05%111.11%


liu hualiu hua21.37%111.11%


stefan agnerstefan agner21.37%111.11%


Total146100.00%9100.00%




EXPORT_SYMBOL(__kunmap_atomic);




void *kmap_atomic_pfn(unsigned long pfn)
{
	unsigned long vaddr;
	int idx, type;
	struct page *page = pfn_to_page(pfn);

	preempt_disable();
	pagefault_disable();
	if (!PageHighMem(page))
		return page_address(page);

	type = kmap_atomic_idx_push();
	idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
	vaddr = __fix_to_virt(idx);
#ifdef CONFIG_DEBUG_HIGHMEM
	BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
#endif
	set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));

	return (void *)vaddr;
}

Contributors
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nicolas pitrenicolas pitre6358.33%114.29%


thomas petazzonithomas petazzoni2422.22%114.29%


peter zijlstrapeter zijlstra109.26%114.29%


rob herringrob herring43.70%114.29%


david hildenbranddavid hildenbrand32.78%114.29%


stefan agnerstefan agner21.85%114.29%


liu hualiu hua21.85%114.29%


Total108100.00%7100.00%




Overall Contributors
PersonTokensPropCommitsCommitProp
nicolas pitrenicolas pitre40169.50%428.57%


liu hualiu hua6010.40%17.14%


peter zijlstrapeter zijlstra386.59%214.29%


rob herringrob herring335.72%17.14%


thomas petazzonithomas petazzoni244.16%17.14%


david hildenbranddavid hildenbrand91.56%17.14%


stefan agnerstefan agner61.04%17.14%


russell kingrussell king40.69%214.29%


americo wangamerico wang20.35%17.14%


Total577100.00%14100.00%

  
Directory: arch/arm/mm