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
  27 extern int mem_init_done;
  28
  29 #define pmd_populate_kernel(mm, pmd, pte) \
  30         set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)))
  31
  32 static 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  */
  43 static 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  */
  62 extern inline pgd_t *pgd_alloc(struct mm_struct *mm)
  63 {
  64         return (pgd_t *)get_zeroed_page(GFP_KERNEL);
  65 }
  66 #endif
  67
  68 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  69 {
  70         free_page((unsigned long)pgd);
  71 }
  72
  73 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address);
  74
  75 static 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
  90 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  91 {
  92         free_page((unsigned long)pte);
  93 }
  94
  95 static inline void pte_free(struct mm_struct *mm, struct page *pte)
  96 {
  97         pgtable_page_dtor(pte);
  98         __free_page(pte);
  99 }
 100
 101 #define __pte_free_tlb(tlb, pte, addr)  \
 102 do {                                    \
 103         pgtable_page_dtor(pte);         \
 104         tlb_remove_page((tlb), (pte));  \
 105 } while (0)
 106
 107 #define pmd_pgtable(pmd) pmd_page(pmd)
 108
 109 #define check_pgt_cache()          do { } while (0)
 110
 111 #endif