1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 */
9#ifndef _ASM_PAGE_H
10#define _ASM_PAGE_H
11
12#include <spaces.h>
13#include <linux/const.h>
14
15/*
16 * PAGE_SHIFT determines the page size
17 */
18#ifdef CONFIG_PAGE_SIZE_4KB
19#define PAGE_SHIFT	12
20#endif
21#ifdef CONFIG_PAGE_SIZE_8KB
22#define PAGE_SHIFT	13
23#endif
24#ifdef CONFIG_PAGE_SIZE_16KB
25#define PAGE_SHIFT	14
26#endif
27#ifdef CONFIG_PAGE_SIZE_32KB
28#define PAGE_SHIFT	15
29#endif
30#ifdef CONFIG_PAGE_SIZE_64KB
31#define PAGE_SHIFT	16
32#endif
33#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
34#define PAGE_MASK       (~((1 << PAGE_SHIFT) - 1))
35
36#ifdef CONFIG_HUGETLB_PAGE
37#define HPAGE_SHIFT	(PAGE_SHIFT + PAGE_SHIFT - 3)
38#define HPAGE_SIZE	(_AC(1,UL) << HPAGE_SHIFT)
39#define HPAGE_MASK	(~(HPAGE_SIZE - 1))
40#define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
41#else /* !CONFIG_HUGETLB_PAGE */
42#define HPAGE_SHIFT	({BUILD_BUG(); 0; })
43#define HPAGE_SIZE	({BUILD_BUG(); 0; })
44#define HPAGE_MASK	({BUILD_BUG(); 0; })
45#define HUGETLB_PAGE_ORDER	({BUILD_BUG(); 0; })
46#endif /* CONFIG_HUGETLB_PAGE */
47
48#ifndef __ASSEMBLY__
49
50#include <linux/pfn.h>
51#include <asm/io.h>
52
53extern void build_clear_page(void);
54extern void build_copy_page(void);
55
56/*
57 * It's normally defined only for FLATMEM config but it's
58 * used in our early mem init code for all memory models.
59 * So always define it.
60 */
61#define ARCH_PFN_OFFSET		PFN_UP(PHYS_OFFSET)
62
63extern void clear_page(void * page);
64extern void copy_page(void * to, void * from);
65
66extern unsigned long shm_align_mask;
67
68static inline unsigned long pages_do_alias(unsigned long addr1,
69	unsigned long addr2)
70{
71	return (addr1 ^ addr2) & shm_align_mask;
72}
73
74struct page;
75
76static inline void clear_user_page(void *addr, unsigned long vaddr,
77	struct page *page)
78{
79	extern void (*flush_data_cache_page)(unsigned long addr);
80
81	clear_page(addr);
82	if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
83		flush_data_cache_page((unsigned long)addr);
84}
85
86extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
87	struct page *to);
88struct vm_area_struct;
89extern void copy_user_highpage(struct page *to, struct page *from,
90	unsigned long vaddr, struct vm_area_struct *vma);
91
92#define __HAVE_ARCH_COPY_USER_HIGHPAGE
93
94/*
95 * These are used to make use of C type-checking..
96 */
97#ifdef CONFIG_64BIT_PHYS_ADDR
98  #ifdef CONFIG_CPU_MIPS32
99    typedef struct { unsigned long pte_low, pte_high; } pte_t;
100    #define pte_val(x)    ((x).pte_low | ((unsigned long long)(x).pte_high << 32))
101    #define __pte(x)      ({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
102  #else
103     typedef struct { unsigned long long pte; } pte_t;
104     #define pte_val(x)	((x).pte)
105     #define __pte(x)	((pte_t) { (x) } )
106  #endif
107#else
108typedef struct { unsigned long pte; } pte_t;
109#define pte_val(x)	((x).pte)
110#define __pte(x)	((pte_t) { (x) } )
111#endif
112typedef struct page *pgtable_t;
113
114/*
115 * Right now we don't support 4-level pagetables, so all pud-related
116 * definitions come from <asm-generic/pgtable-nopud.h>.
117 */
118
119/*
120 * Finall the top of the hierarchy, the pgd
121 */
122typedef struct { unsigned long pgd; } pgd_t;
123#define pgd_val(x)	((x).pgd)
124#define __pgd(x)	((pgd_t) { (x) } )
125
126/*
127 * Manipulate page protection bits
128 */
129typedef struct { unsigned long pgprot; } pgprot_t;
130#define pgprot_val(x)	((x).pgprot)
131#define __pgprot(x)	((pgprot_t) { (x) } )
132
133/*
134 * On R4000-style MMUs where a TLB entry is mapping a adjacent even / odd
135 * pair of pages we only have a single global bit per pair of pages.  When
136 * writing to the TLB make sure we always have the bit set for both pages
137 * or none.  This macro is used to access the `buddy' of the pte we're just
138 * working on.
139 */
140#define ptep_buddy(x)	((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
141
142#endif /* !__ASSEMBLY__ */
143
144/*
145 * __pa()/__va() should be used only during mem init.
146 */
147#ifdef CONFIG_64BIT
148#define __pa(x)								\
149({									\
150    unsigned long __x = (unsigned long)(x);				\
151    __x < CKSEG0 ? XPHYSADDR(__x) : CPHYSADDR(__x);			\
152})
153#else
154#define __pa(x)								\
155    ((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
156#endif
157#define __va(x)		((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
158
159/*
160 * RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
161 * (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org).  The
162 * discussion can be found in lkml posting
163 * <a2ebde260608230500o3407b108hc03debb9da6e62c@mail.gmail.com> which is
164 * archived at http://lists.linuxcoding.com/kernel/2006-q3/msg17360.html
165 *
166 * It is unclear if the misscompilations mentioned in
167 * http://lkml.org/lkml/2010/8/8/138 also affect MIPS so we keep this one
168 * until GCC 3.x has been retired before we can apply
169 * https://patchwork.linux-mips.org/patch/1541/
170 */
171
172#define __pa_symbol(x)	__pa(RELOC_HIDE((unsigned long)(x), 0))
173
174#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
175
176#ifdef CONFIG_FLATMEM
177
178#define pfn_valid(pfn)							\
179({									\
180	unsigned long __pfn = (pfn);					\
181	/* avoid <linux/bootmem.h> include hell */			\
182	extern unsigned long min_low_pfn;				\
183									\
184	__pfn >= min_low_pfn && __pfn < max_mapnr;			\
185})
186
187#elif defined(CONFIG_SPARSEMEM)
188
189/* pfn_valid is defined in linux/mmzone.h */
190
191#elif defined(CONFIG_NEED_MULTIPLE_NODES)
192
193#define pfn_valid(pfn)							\
194({									\
195	unsigned long __pfn = (pfn);					\
196	int __n = pfn_to_nid(__pfn);					\
197	((__n >= 0) ? (__pfn < NODE_DATA(__n)->node_start_pfn +		\
198	                       NODE_DATA(__n)->node_spanned_pages)	\
199	            : 0);						\
200})
201
202#endif
203
204#define virt_to_page(kaddr)	pfn_to_page(PFN_DOWN(virt_to_phys(kaddr)))
205#define virt_addr_valid(kaddr)	pfn_valid(PFN_DOWN(virt_to_phys(kaddr)))
206
207#define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | VM_EXEC | \
208				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
209
210#define UNCAC_ADDR(addr)	((addr) - PAGE_OFFSET + UNCAC_BASE + 	\
211								PHYS_OFFSET)
212#define CAC_ADDR(addr)		((addr) - UNCAC_BASE + PAGE_OFFSET -	\
213								PHYS_OFFSET)
214
215#include <asm-generic/memory_model.h>
216#include <asm-generic/getorder.h>
217
218#endif /* _ASM_PAGE_H */
219