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 /*
18  * PAGE_SHIFT determines the page size
19  */
20 #ifdef CONFIG_PAGE_SIZE_4KB
21 #define PAGE_SHIFT	12
22 #endif
23 #ifdef CONFIG_PAGE_SIZE_8KB
24 #define PAGE_SHIFT	13
25 #endif
26 #ifdef CONFIG_PAGE_SIZE_16KB
27 #define PAGE_SHIFT	14
28 #endif
29 #ifdef CONFIG_PAGE_SIZE_32KB
30 #define PAGE_SHIFT	15
31 #endif
32 #ifdef CONFIG_PAGE_SIZE_64KB
33 #define PAGE_SHIFT	16
34 #endif
35 #define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
36 #define PAGE_MASK	(~((1 << PAGE_SHIFT) - 1))
37 
38 /*
39  * This is used for calculating the real page sizes
40  * for FTLB or VTLB + FTLB configurations.
41  */
page_size_ftlb(unsigned int mmuextdef)42 static inline unsigned int page_size_ftlb(unsigned int mmuextdef)
43 {
44 	switch (mmuextdef) {
45 	case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
46 		if (PAGE_SIZE == (1 << 30))
47 			return 5;
48 		if (PAGE_SIZE == (1llu << 32))
49 			return 6;
50 		if (PAGE_SIZE > (256 << 10))
51 			return 7; /* reserved */
52 		fallthrough;
53 	case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
54 		return (PAGE_SHIFT - 10) / 2;
55 	default:
56 		panic("Invalid FTLB configuration with Conf4_mmuextdef=%d value\n",
57 		      mmuextdef >> 14);
58 	}
59 }
60 
61 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
62 #define HPAGE_SHIFT	(PAGE_SHIFT + PAGE_SHIFT - 3)
63 #define HPAGE_SIZE	(_AC(1,UL) << HPAGE_SHIFT)
64 #define HPAGE_MASK	(~(HPAGE_SIZE - 1))
65 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
66 #else /* !CONFIG_MIPS_HUGE_TLB_SUPPORT */
67 #define HPAGE_SHIFT	({BUILD_BUG(); 0; })
68 #define HPAGE_SIZE	({BUILD_BUG(); 0; })
69 #define HPAGE_MASK	({BUILD_BUG(); 0; })
70 #define HUGETLB_PAGE_ORDER	({BUILD_BUG(); 0; })
71 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
72 
73 #include <linux/pfn.h>
74 
75 extern void build_clear_page(void);
76 extern void build_copy_page(void);
77 
78 /*
79  * It's normally defined only for FLATMEM config but it's
80  * used in our early mem init code for all memory models.
81  * So always define it.
82  */
83 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
84 extern unsigned long ARCH_PFN_OFFSET;
85 # define ARCH_PFN_OFFSET	ARCH_PFN_OFFSET
86 #else
87 # define ARCH_PFN_OFFSET	PFN_UP(PHYS_OFFSET)
88 #endif
89 
90 extern void clear_page(void * page);
91 extern void copy_page(void * to, void * from);
92 
93 extern unsigned long shm_align_mask;
94 
pages_do_alias(unsigned long addr1,unsigned long addr2)95 static inline unsigned long pages_do_alias(unsigned long addr1,
96 	unsigned long addr2)
97 {
98 	return (addr1 ^ addr2) & shm_align_mask;
99 }
100 
101 struct page;
102 
clear_user_page(void * addr,unsigned long vaddr,struct page * page)103 static inline void clear_user_page(void *addr, unsigned long vaddr,
104 	struct page *page)
105 {
106 	extern void (*flush_data_cache_page)(unsigned long addr);
107 
108 	clear_page(addr);
109 	if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
110 		flush_data_cache_page((unsigned long)addr);
111 }
112 
113 struct vm_area_struct;
114 extern void copy_user_highpage(struct page *to, struct page *from,
115 	unsigned long vaddr, struct vm_area_struct *vma);
116 
117 #define __HAVE_ARCH_COPY_USER_HIGHPAGE
118 
119 /*
120  * These are used to make use of C type-checking..
121  */
122 #ifdef CONFIG_PHYS_ADDR_T_64BIT
123   #ifdef CONFIG_CPU_MIPS32
124     typedef struct { unsigned long pte_low, pte_high; } pte_t;
125     #define pte_val(x)	  ((x).pte_low | ((unsigned long long)(x).pte_high << 32))
126     #define __pte(x)	  ({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
127   #else
128      typedef struct { unsigned long long pte; } pte_t;
129      #define pte_val(x) ((x).pte)
130      #define __pte(x)	((pte_t) { (x) } )
131   #endif
132 #else
133 typedef struct { unsigned long pte; } pte_t;
134 #define pte_val(x)	((x).pte)
135 #define __pte(x)	((pte_t) { (x) } )
136 #endif
137 typedef struct page *pgtable_t;
138 
139 /*
140  * Right now we don't support 4-level pagetables, so all pud-related
141  * definitions come from <asm-generic/pgtable-nopud.h>.
142  */
143 
144 /*
145  * Finall the top of the hierarchy, the pgd
146  */
147 typedef struct { unsigned long pgd; } pgd_t;
148 #define pgd_val(x)	((x).pgd)
149 #define __pgd(x)	((pgd_t) { (x) } )
150 
151 /*
152  * Manipulate page protection bits
153  */
154 typedef struct { unsigned long pgprot; } pgprot_t;
155 #define pgprot_val(x)	((x).pgprot)
156 #define __pgprot(x)	((pgprot_t) { (x) } )
157 #define pte_pgprot(x)	__pgprot(pte_val(x) & ~_PFN_MASK)
158 
159 /*
160  * On R4000-style MMUs where a TLB entry is mapping a adjacent even / odd
161  * pair of pages we only have a single global bit per pair of pages.  When
162  * writing to the TLB make sure we always have the bit set for both pages
163  * or none.  This macro is used to access the `buddy' of the pte we're just
164  * working on.
165  */
166 #define ptep_buddy(x)	((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
167 
168 /*
169  * __pa()/__va() should be used only during mem init.
170  */
___pa(unsigned long x)171 static inline unsigned long ___pa(unsigned long x)
172 {
173 	if (IS_ENABLED(CONFIG_64BIT)) {
174 		/*
175 		 * For MIPS64 the virtual address may either be in one of
176 		 * the compatibility segements ckseg0 or ckseg1, or it may
177 		 * be in xkphys.
178 		 */
179 		return x < CKSEG0 ? XPHYSADDR(x) : CPHYSADDR(x);
180 	}
181 
182 	if (!IS_ENABLED(CONFIG_EVA)) {
183 		/*
184 		 * We're using the standard MIPS32 legacy memory map, ie.
185 		 * the address x is going to be in kseg0 or kseg1. We can
186 		 * handle either case by masking out the desired bits using
187 		 * CPHYSADDR.
188 		 */
189 		return CPHYSADDR(x);
190 	}
191 
192 	/*
193 	 * EVA is in use so the memory map could be anything, making it not
194 	 * safe to just mask out bits.
195 	 */
196 	return x - PAGE_OFFSET + PHYS_OFFSET;
197 }
198 #define __pa(x)		___pa((unsigned long)(x))
199 #define __va(x)		((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
200 #include <asm/io.h>
201 
202 /*
203  * RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
204  * (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org).  The
205  * discussion can be found in
206  * https://lore.kernel.org/lkml/a2ebde260608230500o3407b108hc03debb9da6e62c@mail.gmail.com
207  *
208  * It is unclear if the misscompilations mentioned in
209  * https://lore.kernel.org/lkml/1281303490-390-1-git-send-email-namhyung@gmail.com
210  * also affect MIPS so we keep this one until GCC 3.x has been retired
211  * before we can apply https://patchwork.linux-mips.org/patch/1541/
212  */
213 #define __pa_symbol_nodebug(x)	__pa(RELOC_HIDE((unsigned long)(x), 0))
214 
215 #ifdef CONFIG_DEBUG_VIRTUAL
216 extern phys_addr_t __phys_addr_symbol(unsigned long x);
217 #else
218 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
219 #endif
220 
221 #ifndef __pa_symbol
222 #define __pa_symbol(x)		__phys_addr_symbol((unsigned long)(x))
223 #endif
224 
225 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
226 
227 #ifdef CONFIG_FLATMEM
228 
pfn_valid(unsigned long pfn)229 static inline int pfn_valid(unsigned long pfn)
230 {
231 	/* avoid <linux/mm.h> include hell */
232 	extern unsigned long max_mapnr;
233 	unsigned long pfn_offset = ARCH_PFN_OFFSET;
234 
235 	return pfn >= pfn_offset && pfn < max_mapnr;
236 }
237 
238 #elif defined(CONFIG_SPARSEMEM)
239 
240 /* pfn_valid is defined in linux/mmzone.h */
241 
242 #elif defined(CONFIG_NUMA)
243 
244 #define pfn_valid(pfn)							\
245 ({									\
246 	unsigned long __pfn = (pfn);					\
247 	int __n = pfn_to_nid(__pfn);					\
248 	((__n >= 0) ? (__pfn < NODE_DATA(__n)->node_start_pfn +		\
249 			       NODE_DATA(__n)->node_spanned_pages)	\
250 		    : 0);						\
251 })
252 
253 #endif
254 
255 #define virt_to_pfn(kaddr)   	PFN_DOWN(virt_to_phys((void *)(kaddr)))
256 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
257 
258 extern bool __virt_addr_valid(const volatile void *kaddr);
259 #define virt_addr_valid(kaddr)						\
260 	__virt_addr_valid((const volatile void *) (kaddr))
261 
262 #define VM_DATA_DEFAULT_FLAGS	VM_DATA_FLAGS_TSK_EXEC
263 
264 extern unsigned long __kaslr_offset;
kaslr_offset(void)265 static inline unsigned long kaslr_offset(void)
266 {
267 	return __kaslr_offset;
268 }
269 
270 #include <asm-generic/memory_model.h>
271 #include <asm-generic/getorder.h>
272 
273 #endif /* _ASM_PAGE_H */
274