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

   1/*
   2 * include/asm-xtensa/pgalloc.h
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 *
   8 * Copyright (C) 2001-2007 Tensilica Inc.
   9 */
  10
  11#ifndef _XTENSA_PGALLOC_H
  12#define _XTENSA_PGALLOC_H
  13
  14#ifdef __KERNEL__
  15
  16#include <linux/highmem.h>
  17#include <linux/slab.h>
  18
  19/*
  20 * Allocating and freeing a pmd is trivial: the 1-entry pmd is
  21 * inside the pgd, so has no extra memory associated with it.
  22 */
  23
  24#define pmd_populate_kernel(mm, pmdp, ptep)                                  \
  25        (pmd_val(*(pmdp)) = ((unsigned long)ptep))
  26#define pmd_populate(mm, pmdp, page)                                         \
  27        (pmd_val(*(pmdp)) = ((unsigned long)page_to_virt(page)))
  28#define pmd_pgtable(pmd) pmd_page(pmd)
  29
  30static inline pgd_t*
  31pgd_alloc(struct mm_struct *mm)
  32{
  33        return (pgd_t*) __get_free_pages(GFP_KERNEL | __GFP_ZERO, PGD_ORDER);
  34}
  35
  36static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  37{
  38        free_page((unsigned long)pgd);
  39}
  40
  41static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
  42                                         unsigned long address)
  43{
  44        pte_t *ptep;
  45        int i;
  46
  47        ptep = (pte_t *)__get_free_page(GFP_KERNEL);
  48        if (!ptep)
  49                return NULL;
  50        for (i = 0; i < 1024; i++)
  51                pte_clear(NULL, 0, ptep + i);
  52        return ptep;
  53}
  54
  55static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
  56                                        unsigned long addr)
  57{
  58        pte_t *pte;
  59        struct page *page;
  60
  61        pte = pte_alloc_one_kernel(mm, addr);
  62        if (!pte)
  63                return NULL;
  64        page = virt_to_page(pte);
  65        if (!pgtable_page_ctor(page)) {
  66                __free_page(page);
  67                return NULL;
  68        }
  69        return page;
  70}
  71
  72static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  73{
  74        free_page((unsigned long)pte);
  75}
  76
  77static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
  78{
  79        pgtable_page_dtor(pte);
  80        __free_page(pte);
  81}
  82#define pmd_pgtable(pmd) pmd_page(pmd)
  83
  84#endif /* __KERNEL__ */
  85#endif /* _XTENSA_PGALLOC_H */
  86