xref: /openbmc/linux/arch/xtensa/include/asm/pgalloc.h (revision b627b4ed)
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 
18 /*
19  * Allocating and freeing a pmd is trivial: the 1-entry pmd is
20  * inside the pgd, so has no extra memory associated with it.
21  */
22 
23 #define pmd_populate_kernel(mm, pmdp, ptep)				     \
24 	(pmd_val(*(pmdp)) = ((unsigned long)ptep))
25 #define pmd_populate(mm, pmdp, page)					     \
26 	(pmd_val(*(pmdp)) = ((unsigned long)page_to_virt(page)))
27 #define pmd_pgtable(pmd) pmd_page(pmd)
28 
29 static inline pgd_t*
30 pgd_alloc(struct mm_struct *mm)
31 {
32 	return (pgd_t*) __get_free_pages(GFP_KERNEL | __GFP_ZERO, PGD_ORDER);
33 }
34 
35 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
36 {
37 	free_page((unsigned long)pgd);
38 }
39 
40 /* Use a slab cache for the pte pages (see also sparc64 implementation) */
41 
42 extern struct kmem_cache *pgtable_cache;
43 
44 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
45 					 unsigned long address)
46 {
47 	return kmem_cache_alloc(pgtable_cache, GFP_KERNEL|__GFP_REPEAT);
48 }
49 
50 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
51 					unsigned long addr)
52 {
53 	struct page *page;
54 
55 	page = virt_to_page(pte_alloc_one_kernel(mm, addr));
56 	pgtable_page_ctor(page);
57 	return page;
58 }
59 
60 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
61 {
62 	kmem_cache_free(pgtable_cache, pte);
63 }
64 
65 static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
66 {
67 	pgtable_page_dtor(pte);
68 	kmem_cache_free(pgtable_cache, page_address(pte));
69 }
70 #define pmd_pgtable(pmd) pmd_page(pmd)
71 
72 #endif /* __KERNEL__ */
73 #endif /* _XTENSA_PGALLOC_H */
74