LXR linux/arch/openrisc/include/asm/pgalloc.h

   1/*
   2 * OpenRISC Linux
   3 *
   4 * Linux architectural port borrowing liberally from similar works of
   5 * others.  All original copyrights apply as per the original source
   6 * declaration.
   7 *
   8 * OpenRISC implementation:
   9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
  10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
  11 * et al.
  12 *
  13 * This program is free software; you can redistribute it and/or modify
  14 * it under the terms of the GNU General Public License as published by
  15 * the Free Software Foundation; either version 2 of the License, or
  16 * (at your option) any later version.
  17 */
  18
  19#ifndef __ASM_OPENRISC_PGALLOC_H
  20#define __ASM_OPENRISC_PGALLOC_H
  21
  22#include <asm/page.h>
  23#include <linux/threads.h>
  24#include <linux/mm.h>
  25#include <linux/memblock.h>
  26
  27extern int mem_init_done;
  28
  29#define pmd_populate_kernel(mm, pmd, pte) \
  30        set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)))
  31
  32static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
  33                                struct page *pte)
  34{
  35        set_pmd(pmd, __pmd(_KERNPG_TABLE +
  36                     ((unsigned long)page_to_pfn(pte) <<
  37                     (unsigned long) PAGE_SHIFT)));
  38}
  39
  40/*
  41 * Allocate and free page tables.
  42 */
  43static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  44{
  45        pgd_t *ret = (pgd_t *)__get_free_page(GFP_KERNEL);
  46
  47        if (ret) {
  48                memset(ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
  49                memcpy(ret + USER_PTRS_PER_PGD,
  50                       swapper_pg_dir + USER_PTRS_PER_PGD,
  51                       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
  52
  53        }
  54        return ret;
  55}
  56
  57#if 0
  58/* FIXME: This seems to be the preferred style, but we are using
  59 * current_pgd (from mm->pgd) to load kernel pages so we need it
  60 * initialized.  This needs to be looked into.
  61 */
  62extern inline pgd_t *pgd_alloc(struct mm_struct *mm)
  63{
  64        return (pgd_t *)get_zeroed_page(GFP_KERNEL);
  65}
  66#endif
  67
  68static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  69{
  70        free_page((unsigned long)pgd);
  71}
  72
  73extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address);
  74
  75static inline struct page *pte_alloc_one(struct mm_struct *mm,
  76                                         unsigned long address)
  77{
  78        struct page *pte;
  79        pte = alloc_pages(GFP_KERNEL, 0);
  80        if (!pte)
  81                return NULL;
  82        clear_page(page_address(pte));
  83        if (!pgtable_page_ctor(pte)) {
  84                __free_page(pte);
  85                return NULL;
  86        }
  87        return pte;
  88}
  89
  90static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  91{
  92        free_page((unsigned long)pte);
  93}
  94
  95static inline void pte_free(struct mm_struct *mm, struct page *pte)
  96{
  97        pgtable_page_dtor(pte);
  98        __free_page(pte);
  99}
 100
 101
 102#define __pte_free_tlb(tlb, pte, addr) tlb_remove_page((tlb), (pte))
 103#define pmd_pgtable(pmd) pmd_page(pmd)
 104
 105#define check_pgt_cache()          do { } while (0)
 106
 107#endif
 108