xref: /openbmc/linux/arch/xtensa/include/asm/pgalloc.h (revision b6bec26c)
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 
30 static inline pgd_t*
31 pgd_alloc(struct mm_struct *mm)
32 {
33 	return (pgd_t*) __get_free_pages(GFP_KERNEL | __GFP_ZERO, PGD_ORDER);
34 }
35 
36 static 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 
43 extern struct kmem_cache *pgtable_cache;
44 
45 static 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 
51 static 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 
61 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
62 {
63 	kmem_cache_free(pgtable_cache, pte);
64 }
65 
66 static 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