xref: /linux/arch/mips/include/asm/page.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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       (~(PAGE_SIZE - 1))
35 
36 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
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_MIPS_HUGE_TLB_SUPPORT */
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_MIPS_HUGE_TLB_SUPPORT */
47 
48 #ifndef __ASSEMBLY__
49 
50 #include <linux/pfn.h>
51 #include <asm/io.h>
52 
53 extern void build_clear_page(void);
54 extern 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 
63 extern void clear_page(void * page);
64 extern void copy_page(void * to, void * from);
65 
66 extern unsigned long shm_align_mask;
67 
68 static inline unsigned long pages_do_alias(unsigned long addr1,
69 	unsigned long addr2)
70 {
71 	return (addr1 ^ addr2) & shm_align_mask;
72 }
73 
74 struct page;
75 
76 static 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 
86 extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
87 	struct page *to);
88 struct vm_area_struct;
89 extern 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
108 typedef struct { unsigned long pte; } pte_t;
109 #define pte_val(x)	((x).pte)
110 #define __pte(x)	((pte_t) { (x) } )
111 #endif
112 typedef 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  */
122 typedef 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  */
129 typedef 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