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
  41/* Use a slab cache for the pte pages (see also sparc64 implementation) */
  42
  43extern struct kmem_cache *pgtable_cache;
  44
  45static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
  46                                         unsigned long address)
  47{
  48        return kmem_cache_alloc(pgtable_cache, GFP_KERNEL|__GFP_REPEAT);
  49}
  50
  51static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
  52                                        unsigned long addr)
  53{
  54        struct page *page;
  55
  56        page = virt_to_page(pte_alloc_one_kernel(mm, addr));
  57        pgtable_page_ctor(page);
  58        return page;
  59}
  60
  61static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  62{
  63        kmem_cache_free(pgtable_cache, pte);
  64}
  65
  66static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
  67{
  68        pgtable_page_dtor(pte);
  69        kmem_cache_free(pgtable_cache, page_address(pte));
  70}
  71#define pmd_pgtable(pmd) pmd_page(pmd)
  72
  73#endif /* __KERNEL__ */
  74#endif /* _XTENSA_PGALLOC_H */
  75