1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 */
6#include <linux/export.h>
7#include <linux/mm.h>
8#include <linux/string.h>
9#include <asm/pgalloc.h>
10
11pgd_t *pgd_alloc(struct mm_struct *mm)
12{
13	pgd_t *init, *ret = NULL;
14	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM,
15			PGD_TABLE_ORDER);
16
17	if (ptdesc) {
18		ret = ptdesc_address(ptdesc);
19		init = pgd_offset(&init_mm, 0UL);
20		pgd_init(ret);
21		memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
22		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
23	}
24
25	return ret;
26}
27EXPORT_SYMBOL_GPL(pgd_alloc);
28