1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_PGALLOC_H
3 #define _ASM_PGALLOC_H
4 
5 #include <linux/gfp.h>
6 #include <linux/mm.h>
7 #include <linux/threads.h>
8 #include <asm/processor.h>
9 #include <asm/fixmap.h>
10 
11 #include <asm/cache.h>
12 
13 #define __HAVE_ARCH_PMD_ALLOC_ONE
14 #define __HAVE_ARCH_PMD_FREE
15 #define __HAVE_ARCH_PGD_FREE
16 #include <asm-generic/pgalloc.h>
17 
18 /* Allocate the top level pgd (page directory) */
pgd_alloc(struct mm_struct * mm)19 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
20 {
21 	pgd_t *pgd;
22 
23 	pgd = (pgd_t *) __get_free_pages(GFP_KERNEL, PGD_ORDER);
24 	if (unlikely(pgd == NULL))
25 		return NULL;
26 
27 	memset(pgd, 0, PAGE_SIZE << PGD_ORDER);
28 
29 	return pgd;
30 }
31 
pgd_free(struct mm_struct * mm,pgd_t * pgd)32 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
33 {
34 	free_pages((unsigned long)pgd, PGD_ORDER);
35 }
36 
37 #if CONFIG_PGTABLE_LEVELS == 3
38 
39 /* Three Level Page Table Support for pmd's */
40 
pud_populate(struct mm_struct * mm,pud_t * pud,pmd_t * pmd)41 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
42 {
43 	set_pud(pud, __pud((PxD_FLAG_PRESENT | PxD_FLAG_VALID) +
44 			(__u32)(__pa((unsigned long)pmd) >> PxD_VALUE_SHIFT)));
45 }
46 
pmd_alloc_one(struct mm_struct * mm,unsigned long address)47 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
48 {
49 	pmd_t *pmd;
50 
51 	pmd = (pmd_t *)__get_free_pages(GFP_PGTABLE_KERNEL, PMD_ORDER);
52 	if (likely(pmd))
53 		memset ((void *)pmd, 0, PAGE_SIZE << PMD_ORDER);
54 	return pmd;
55 }
56 
pmd_free(struct mm_struct * mm,pmd_t * pmd)57 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
58 {
59 	free_pages((unsigned long)pmd, PMD_ORDER);
60 }
61 #endif
62 
63 static inline void
pmd_populate_kernel(struct mm_struct * mm,pmd_t * pmd,pte_t * pte)64 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
65 {
66 	set_pmd(pmd, __pmd((PxD_FLAG_PRESENT | PxD_FLAG_VALID)
67 		+ (__u32)(__pa((unsigned long)pte) >> PxD_VALUE_SHIFT)));
68 }
69 
70 #define pmd_populate(mm, pmd, pte_page) \
71 	pmd_populate_kernel(mm, pmd, page_address(pte_page))
72 #define pmd_pgtable(pmd) pmd_page(pmd)
73 
74 #endif
75