Release 4.11 arch/arm/mm/pgd.c

/*
 *  linux/arch/arm/mm/pgd.c
 *
 *  Copyright (C) 1998-2005 Russell King
 *
 * 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/mm.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/slab.h>

#include <asm/cp15.h>
#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/tlbflush.h>

#include "mm.h"

#ifdef CONFIG_ARM_LPAE

#define __pgd_alloc()	kmalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL)

#define __pgd_free(pgd)	kfree(pgd)
#else

#define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL, 2)

#define __pgd_free(pgd)	free_pages((unsigned long)pgd, 2)
#endif

/*
 * need to get a 16k page for level 1
 */


pgd_t *pgd_alloc(struct mm_struct *mm)
{
	pgd_t *new_pgd, *init_pgd;
	pud_t *new_pud, *init_pud;
	pmd_t *new_pmd, *init_pmd;
	pte_t *new_pte, *init_pte;

	new_pgd = __pgd_alloc();
	if (!new_pgd)
		goto no_pgd;

	memset(new_pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));

	/*
         * Copy over the kernel and IO PGD entries
         */
	init_pgd = pgd_offset_k(0);
	memcpy(new_pgd + USER_PTRS_PER_PGD, init_pgd + USER_PTRS_PER_PGD,
		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));

	clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));

#ifdef CONFIG_ARM_LPAE
	/*
         * Allocate PMD table for modules and pkmap mappings.
         */
	new_pud = pud_alloc(mm, new_pgd + pgd_index(MODULES_VADDR),
			    MODULES_VADDR);
	if (!new_pud)
		goto no_pud;

	new_pmd = pmd_alloc(mm, new_pud, 0);
	if (!new_pmd)
		goto no_pmd;
#endif

	if (!vectors_high()) {
		/*
                 * On ARM, first page must always be allocated since it
                 * contains the machine vectors. The vectors are always high
                 * with LPAE.
                 */
		new_pud = pud_alloc(mm, new_pgd, 0);
		if (!new_pud)
			goto no_pud;

		new_pmd = pmd_alloc(mm, new_pud, 0);
		if (!new_pmd)
			goto no_pmd;

		new_pte = pte_alloc_map(mm, new_pmd, 0);
		if (!new_pte)
			goto no_pte;

#ifndef CONFIG_ARM_LPAE
		/*
                 * Modify the PTE pointer to have the correct domain.  This
                 * needs to be the vectors domain to avoid the low vectors
                 * being unmapped.
                 */
		pmd_val(*new_pmd) &= ~PMD_DOMAIN_MASK;
		pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS);
#endif

		init_pud = pud_offset(init_pgd, 0);
		init_pmd = pmd_offset(init_pud, 0);
		init_pte = pte_offset_map(init_pmd, 0);
		set_pte_ext(new_pte + 0, init_pte[0], 0);
		set_pte_ext(new_pte + 1, init_pte[1], 0);
		pte_unmap(init_pte);
		pte_unmap(new_pte);
	}

	return new_pgd;

no_pte:
	pmd_free(mm, new_pmd);
	mm_dec_nr_pmds(mm);
no_pmd:
	pud_free(mm, new_pud);
no_pud:
	__pgd_free(new_pgd);
no_pgd:
	return NULL;
}

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Linus Torvalds (pre-git)
47
13.35%
3
15.79%
Linus Torvalds
31
8.81%
2
10.53%
Kirill A. Shutemov
5
1.42%
1
5.26%
Benjamin Herrenschmidt
2
0.57%
1
5.26%
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2
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352
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19
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void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pgtable_t pte;

	if (!pgd_base)
		return;

	pgd = pgd_base + pgd_index(0);
	if (pgd_none_or_clear_bad(pgd))
		goto no_pgd;

	pud = pud_offset(pgd, 0);
	if (pud_none_or_clear_bad(pud))
		goto no_pud;

	pmd = pmd_offset(pud, 0);
	if (pmd_none_or_clear_bad(pmd))
		goto no_pmd;

	pte = pmd_pgtable(*pmd);
	pmd_clear(pmd);
	pte_free(mm, pte);
	atomic_long_dec(&mm->nr_ptes);
no_pmd:
	pud_clear(pud);
	pmd_free(mm, pmd);
	mm_dec_nr_pmds(mm);
no_pud:
	pgd_clear(pgd);
	pud_free(mm, pud);
no_pgd:
#ifdef CONFIG_ARM_LPAE
	/*
         * Free modules/pkmap or identity pmd tables.
         */
	for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
		if (pgd_none_or_clear_bad(pgd))
			continue;
		if (pgd_val(*pgd) & L_PGD_SWAPPER)
			continue;
		pud = pud_offset(pgd, 0);
		if (pud_none_or_clear_bad(pud))
			continue;
		pmd = pmd_offset(pud, 0);
		pud_clear(pud);
		pmd_free(mm, pmd);
		mm_dec_nr_pmds(mm);
		pgd_clear(pgd);
		pud_free(mm, pud);
	}
#endif
	__pgd_free(pgd_base);
}
Contributors
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Catalin Marinas
93
36.19%
1
7.69%
Russell King
74
28.79%
5
38.46%
Linus Torvalds (pre-git)
38
14.79%
2
15.38%
Linus Torvalds
23
8.95%
2
15.38%
Kirill A. Shutemov
18
7.00%
1
7.69%
Benjamin Herrenschmidt
9
3.50%
1
7.69%
Uwe Kleine-König
2
0.78%
1
7.69%
Total
257
100.00%
13
100.00%

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Russell King
298
44.54%
16
55.17%
Catalin Marinas
179
26.76%
1
3.45%
Linus Torvalds (pre-git)
96
14.35%
4
13.79%
Linus Torvalds
54
8.07%
2
6.90%
Kirill A. Shutemov
23
3.44%
1
3.45%
Benjamin Herrenschmidt
11
1.64%
1
3.45%
Tejun Heo
3
0.45%
1
3.45%
Uwe Kleine-König
2
0.30%
1
3.45%
Peter Zijlstra
2
0.30%
1
3.45%
Michal Hocko
1
0.15%
1
3.45%
Total
669
100.00%
29
100.00%
Directory: arch/arm/mm

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