/* * PGD allocation/freeing * * Copyright (C) 2012 ARM Ltd. * Author: Catalin Marinas <catalin.marinas@arm.com> * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/mm.h> #include <linux/gfp.h> #include <linux/highmem.h> #include <linux/slab.h> #include <asm/pgalloc.h> #include <asm/page.h> #include <asm/tlbflush.h> #include "mm.h" #define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t)) static struct kmem_cache *pgd_cache; pgd_t *pgd_alloc(struct mm_struct *mm) { if (PGD_SIZE == PAGE_SIZE) return (pgd_t *)__get_free_page(PGALLOC_GFP); else return kmem_cache_alloc(pgd_cache, PGALLOC_GFP); } void pgd_free(struct mm_struct *mm, pgd_t *pgd) { if (PGD_SIZE == PAGE_SIZE) free_page((unsigned long)pgd); else kmem_cache_free(pgd_cache, pgd); } static int __init pgd_cache_init(void) { /* * Naturally aligned pgds required by the architecture. */ if (PGD_SIZE != PAGE_SIZE) pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE, SLAB_PANIC, NULL); return 0; } core_initcall(pgd_cache_init);