pgalloc.h

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * OpenRISC Linux
 4 *
 5 * Linux architectural port borrowing liberally from similar works of
 6 * others.  All original copyrights apply as per the original source
 7 * declaration.
 8 *
 9 * OpenRISC implementation:
10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12 * et al.
13 */
14
15#ifndef __ASM_OPENRISC_PGALLOC_H
16#define __ASM_OPENRISC_PGALLOC_H
17
18#include <asm/page.h>
19#include <linux/threads.h>
20#include <linux/mm.h>
21#include <linux/memblock.h>
22
23#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
24#include <asm-generic/pgalloc.h>
25
26extern int mem_init_done;
27
28#define pmd_populate_kernel(mm, pmd, pte) \
29	set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)))
30
31static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
32				struct page *pte)
33{
34	set_pmd(pmd, __pmd(_KERNPG_TABLE +
35		     ((unsigned long)page_to_pfn(pte) <<
36		     (unsigned long) PAGE_SHIFT)));
37}
38
39/*
40 * Allocate and free page tables.
41 */
42static inline pgd_t *pgd_alloc(struct mm_struct *mm)
43{
44	pgd_t *ret = __pgd_alloc(mm, 0);
45
46	if (ret)
47		memcpy(ret + USER_PTRS_PER_PGD,
48		       swapper_pg_dir + USER_PTRS_PER_PGD,
49		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
50
51	return ret;
52}
53
54#if 0
55/* FIXME: This seems to be the preferred style, but we are using
56 * current_pgd (from mm->pgd) to load kernel pages so we need it
57 * initialized.  This needs to be looked into.
58 */
59extern inline pgd_t *pgd_alloc(struct mm_struct *mm)
60{
61	return (pgd_t *)get_zeroed_page(GFP_KERNEL);
62}
63#endif
64
65extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
66
67#define __pte_free_tlb(tlb, pte, addr)	\
68	tlb_remove_ptdesc((tlb), page_ptdesc(pte))
69
70#endif