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 */