| 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 | |
| 11 | pgd_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 | order: PGD_TABLE_ORDER); |
| 16 | |
| 17 | if (ptdesc) { |
| 18 | ret = ptdesc_address(pt: 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 | } |
| 27 | EXPORT_SYMBOL_GPL(pgd_alloc); |
| 28 |