From 0c668984ddff94f800b37f244d7b21074b04b971 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 27 Sep 2006 15:40:28 +0100 Subject: [ARM] Rename mm-armv.c to pgd.c mm-armv.c now only contains the pgd allocation/freeing code, so rename it to have a more sensible filename. Signed-off-by: Russell King --- arch/arm/mm/pgd.c | 101 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 arch/arm/mm/pgd.c (limited to 'arch/arm/mm/pgd.c') diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c new file mode 100644 index 00000000000..20c1b0df75f --- /dev/null +++ b/arch/arm/mm/pgd.c @@ -0,0 +1,101 @@ +/* + * 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 +#include + +#include +#include +#include + +#include "mm.h" + +#define FIRST_KERNEL_PGD_NR (FIRST_USER_PGD_NR + USER_PTRS_PER_PGD) + +/* + * need to get a 16k page for level 1 + */ +pgd_t *get_pgd_slow(struct mm_struct *mm) +{ + pgd_t *new_pgd, *init_pgd; + pmd_t *new_pmd, *init_pmd; + pte_t *new_pte, *init_pte; + + new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2); + if (!new_pgd) + goto no_pgd; + + memzero(new_pgd, FIRST_KERNEL_PGD_NR * sizeof(pgd_t)); + + /* + * Copy over the kernel and IO PGD entries + */ + init_pgd = pgd_offset_k(0); + memcpy(new_pgd + FIRST_KERNEL_PGD_NR, init_pgd + FIRST_KERNEL_PGD_NR, + (PTRS_PER_PGD - FIRST_KERNEL_PGD_NR) * sizeof(pgd_t)); + + clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t)); + + if (!vectors_high()) { + /* + * On ARM, first page must always be allocated since it + * contains the machine vectors. + */ + new_pmd = pmd_alloc(mm, new_pgd, 0); + if (!new_pmd) + goto no_pmd; + + new_pte = pte_alloc_map(mm, new_pmd, 0); + if (!new_pte) + goto no_pte; + + init_pmd = pmd_offset(init_pgd, 0); + init_pte = pte_offset_map_nested(init_pmd, 0); + set_pte(new_pte, *init_pte); + pte_unmap_nested(init_pte); + pte_unmap(new_pte); + } + + return new_pgd; + +no_pte: + pmd_free(new_pmd); +no_pmd: + free_pages((unsigned long)new_pgd, 2); +no_pgd: + return NULL; +} + +void free_pgd_slow(pgd_t *pgd) +{ + pmd_t *pmd; + struct page *pte; + + if (!pgd) + return; + + /* pgd is always present and good */ + pmd = pmd_off(pgd, 0); + if (pmd_none(*pmd)) + goto free; + if (pmd_bad(*pmd)) { + pmd_ERROR(*pmd); + pmd_clear(pmd); + goto free; + } + + pte = pmd_page(*pmd); + pmd_clear(pmd); + dec_zone_page_state(virt_to_page((unsigned long *)pgd), NR_PAGETABLE); + pte_lock_deinit(pte); + pte_free(pte); + pmd_free(pmd); +free: + free_pages((unsigned long) pgd, 2); +} -- cgit v1.2.3