xref: /linux/arch/mips/include/asm/page.h (revision 6aacab308a5dfd222b2d23662bbae60c11007cfb)
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 #include <linux/kernel.h>
15 #include <asm/mipsregs.h>
16 
17 #include <vdso/page.h>
18 
19 /*
20  * This is used for calculating the real page sizes
21  * for FTLB or VTLB + FTLB configurations.
22  */
23 static inline unsigned int page_size_ftlb(unsigned int mmuextdef)
24 {
25 	switch (mmuextdef) {
26 	case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
27 		if (PAGE_SIZE == (1 << 30))
28 			return 5;
29 		if (PAGE_SIZE == (1llu << 32))
30 			return 6;
31 		if (PAGE_SIZE > (256 << 10))
32 			return 7; /* reserved */
33 		fallthrough;
34 	case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
35 		return (PAGE_SHIFT - 10) / 2;
36 	default:
37 		panic("Invalid FTLB configuration with Conf4_mmuextdef=%d value\n",
38 		      mmuextdef >> 14);
39 	}
40 }
41 
42 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
43 #define HPAGE_SHIFT	(PAGE_SHIFT + PAGE_SHIFT - 3)
44 #define HPAGE_SIZE	(_AC(1,UL) << HPAGE_SHIFT)
45 #define HPAGE_MASK	(~(HPAGE_SIZE - 1))
46 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
47 #else /* !CONFIG_MIPS_HUGE_TLB_SUPPORT */
48 #define HPAGE_SHIFT	({BUILD_BUG(); 0; })
49 #define HPAGE_SIZE	({BUILD_BUG(); 0; })
50 #define HPAGE_MASK	({BUILD_BUG(); 0; })
51 #define HUGETLB_PAGE_ORDER	({BUILD_BUG(); 0; })
52 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
53 
54 #include <linux/pfn.h>
55 
56 extern void build_clear_page(void);
57 extern void build_copy_page(void);
58 
59 /*
60  * It's normally defined only for FLATMEM config but it's
61  * used in our early mem init code for all memory models.
62  * So always define it.
63  */
64 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
65 extern unsigned long ARCH_PFN_OFFSET;
66 # define ARCH_PFN_OFFSET	ARCH_PFN_OFFSET
67 #else
68 # define ARCH_PFN_OFFSET	PFN_UP(PHYS_OFFSET)
69 #endif
70 
71 extern void clear_page(void * page);
72 extern void copy_page(void * to, void * from);
73 
74 extern unsigned long shm_align_mask;
75 
76 static inline unsigned long pages_do_alias(unsigned long addr1,
77 	unsigned long addr2)
78 {
79 	return (addr1 ^ addr2) & shm_align_mask;
80 }
81 
82 struct page;
83 
84 static inline void clear_user_page(void *addr, unsigned long vaddr,
85 	struct page *page)
86 {
87 	extern void (*flush_data_cache_page)(unsigned long addr);
88 
89 	clear_page(addr);
90 	if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
91 		flush_data_cache_page((unsigned long)addr);
92 }
93 #define clear_user_page clear_user_page
94 
95 struct vm_area_struct;
96 extern void copy_user_highpage(struct page *to, struct page *from,
97 	unsigned long vaddr, struct vm_area_struct *vma);
98 
99 #define __HAVE_ARCH_COPY_USER_HIGHPAGE
100 
101 /*
102  * These are used to make use of C type-checking..
103  */
104 #ifdef CONFIG_PHYS_ADDR_T_64BIT
105   #ifdef CONFIG_CPU_MIPS32
106     typedef struct { unsigned long pte_low, pte_high; } pte_t;
107     #define pte_val(x)	  ((x).pte_low | ((unsigned long long)(x).pte_high << 32))
108     #define __pte(x)	  ({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
109   #else
110      typedef struct { unsigned long long pte; } pte_t;
111      #define pte_val(x) ((x).pte)
112      #define __pte(x)	((pte_t) { (x) } )
113   #endif
114 #else
115 typedef struct { unsigned long pte; } pte_t;
116 #define pte_val(x)	((x).pte)
117 #define __pte(x)	((pte_t) { (x) } )
118 #endif
119 typedef struct page *pgtable_t;
120 
121 /*
122  * Right now we don't support 4-level pagetables, so all pud-related
123  * definitions come from <asm-generic/pgtable-nopud.h>.
124  */
125 
126 /*
127  * Finall the top of the hierarchy, the pgd
128  */
129 typedef struct { unsigned long pgd; } pgd_t;
130 #define pgd_val(x)	((x).pgd)
131 #define __pgd(x)	((pgd_t) { (x) } )
132 
133 /*
134  * Manipulate page protection bits
135  */
136 typedef struct { unsigned long pgprot; } pgprot_t;
137 #define pgprot_val(x)	((x).pgprot)
138 #define __pgprot(x)	((pgprot_t) { (x) } )
139 #define pte_pgprot(x)	__pgprot(pte_val(x) & ~_PFN_MASK)
140 
141 /*
142  * On R4000-style MMUs where a TLB entry is mapping a adjacent even / odd
143  * pair of pages we only have a single global bit per pair of pages.  When
144  * writing to the TLB make sure we always have the bit set for both pages
145  * or none.  This macro is used to access the `buddy' of the pte we're just
146  * working on.
147  */
148 #define ptep_buddy(x)	((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
149 
150 /*
151  * __pa()/__va() should be used only during mem init.
152  */
153 static inline unsigned long ___pa(unsigned long x)
154 {
155 	if (IS_ENABLED(CONFIG_64BIT)) {
156 		/*
157 		 * For MIPS64 the virtual address may either be in one of
158 		 * the compatibility segments ckseg0 or ckseg1, or it may
159 		 * be in xkphys.
160 		 */
161 		return x < CKSEG0 ? XPHYSADDR(x) : CPHYSADDR(x);
162 	}
163 
164 	if (!IS_ENABLED(CONFIG_EVA)) {
165 		/*
166 		 * We're using the standard MIPS32 legacy memory map, ie.
167 		 * the address x is going to be in kseg0 or kseg1. We can
168 		 * handle either case by masking out the desired bits using
169 		 * CPHYSADDR.
170 		 */
171 		return CPHYSADDR(x);
172 	}
173 
174 	/*
175 	 * EVA is in use so the memory map could be anything, making it not
176 	 * safe to just mask out bits.
177 	 */
178 	return x - PAGE_OFFSET + PHYS_OFFSET;
179 }
180 #define __pa(x)		___pa((unsigned long)(x))
181 #define __va(x)		((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
182 #include <asm/io.h>
183 
184 /*
185  * RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
186  * (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org).  The
187  * discussion can be found in
188  * https://lore.kernel.org/lkml/a2ebde260608230500o3407b108hc03debb9da6e62c@mail.gmail.com
189  *
190  * It is unclear if the misscompilations mentioned in
191  * https://lore.kernel.org/lkml/1281303490-390-1-git-send-email-namhyung@gmail.com
192  * also affect MIPS so we keep this one until GCC 3.x has been retired
193  * before we can apply https://patchwork.linux-mips.org/patch/1541/
194  */
195 #define __pa_symbol_nodebug(x)	__pa(RELOC_HIDE((unsigned long)(x), 0))
196 
197 #ifdef CONFIG_DEBUG_VIRTUAL
198 extern phys_addr_t __phys_addr_symbol(unsigned long x);
199 #else
200 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
201 #endif
202 
203 #ifndef __pa_symbol
204 #define __pa_symbol(x)		__phys_addr_symbol((unsigned long)(x))
205 #endif
206 
207 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
208 
209 #define virt_to_pfn(kaddr)   	PFN_DOWN(virt_to_phys((void *)(kaddr)))
210 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
211 
212 extern bool __virt_addr_valid(const volatile void *kaddr);
213 #define virt_addr_valid(kaddr)						\
214 	__virt_addr_valid((const volatile void *) (kaddr))
215 
216 #define VM_DATA_DEFAULT_FLAGS	VM_DATA_FLAGS_TSK_EXEC
217 
218 extern unsigned long __kaslr_offset;
219 static inline unsigned long kaslr_offset(void)
220 {
221 	return __kaslr_offset;
222 }
223 
224 #include <asm-generic/memory_model.h>
225 #include <asm-generic/getorder.h>
226 
227 #endif /* _ASM_PAGE_H */
228