1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 4 * Copyright 2003 PathScale, Inc. 5 * Derived from include/asm-i386/pgtable.h 6 */ 7 8 #ifndef __UM_PGTABLE_H 9 #define __UM_PGTABLE_H 10 11 #include <asm/fixmap.h> 12 13 #define _PAGE_PRESENT 0x001 14 #define _PAGE_NEWPAGE 0x002 15 #define _PAGE_NEWPROT 0x004 16 #define _PAGE_RW 0x020 17 #define _PAGE_USER 0x040 18 #define _PAGE_ACCESSED 0x080 19 #define _PAGE_DIRTY 0x100 20 /* If _PAGE_PRESENT is clear, we use these: */ 21 #define _PAGE_PROTNONE 0x010 /* if the user mapped it with PROT_NONE; 22 pte_present gives true */ 23 24 #ifdef CONFIG_3_LEVEL_PGTABLES 25 #include <asm/pgtable-3level.h> 26 #else 27 #include <asm/pgtable-2level.h> 28 #endif 29 30 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 31 32 /* zero page used for uninitialized stuff */ 33 extern unsigned long *empty_zero_page; 34 35 /* Just any arbitrary offset to the start of the vmalloc VM area: the 36 * current 8MB value just means that there will be a 8MB "hole" after the 37 * physical memory until the kernel virtual memory starts. That means that 38 * any out-of-bounds memory accesses will hopefully be caught. 39 * The vmalloc() routines leaves a hole of 4kB between each vmalloced 40 * area for the same reason. ;) 41 */ 42 43 extern unsigned long end_iomem; 44 45 #define VMALLOC_OFFSET (__va_space) 46 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 47 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK) 48 #define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE) 49 #define MODULES_VADDR VMALLOC_START 50 #define MODULES_END VMALLOC_END 51 #define MODULES_LEN (MODULES_VADDR - MODULES_END) 52 53 #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY) 54 #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) 55 #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) 56 #define __PAGE_KERNEL_EXEC \ 57 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 58 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED) 59 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED) 60 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 61 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 62 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 63 #define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC) 64 65 /* 66 * The i386 can't do page protection for execute, and considers that the same 67 * are read. 68 * Also, write permissions imply read permissions. This is the closest we can 69 * get.. 70 */ 71 72 /* 73 * ZERO_PAGE is a global shared page that is always zero: used 74 * for zero-mapped memory areas etc.. 75 */ 76 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page) 77 78 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE)) 79 80 #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE)) 81 #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE) 82 83 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT) 84 #define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0) 85 86 #define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE) 87 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE) 88 89 #define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE) 90 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE) 91 92 #define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE) 93 #define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE) 94 95 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) 96 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK) 97 98 #define pte_page(x) pfn_to_page(pte_pfn(x)) 99 100 #define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE)) 101 102 /* 103 * ================================= 104 * Flags checking section. 105 * ================================= 106 */ 107 108 static inline int pte_none(pte_t pte) 109 { 110 return pte_is_zero(pte); 111 } 112 113 /* 114 * The following only work if pte_present() is true. 115 * Undefined behaviour if not.. 116 */ 117 static inline int pte_read(pte_t pte) 118 { 119 return((pte_get_bits(pte, _PAGE_USER)) && 120 !(pte_get_bits(pte, _PAGE_PROTNONE))); 121 } 122 123 static inline int pte_exec(pte_t pte){ 124 return((pte_get_bits(pte, _PAGE_USER)) && 125 !(pte_get_bits(pte, _PAGE_PROTNONE))); 126 } 127 128 static inline int pte_write(pte_t pte) 129 { 130 return((pte_get_bits(pte, _PAGE_RW)) && 131 !(pte_get_bits(pte, _PAGE_PROTNONE))); 132 } 133 134 static inline int pte_dirty(pte_t pte) 135 { 136 return pte_get_bits(pte, _PAGE_DIRTY); 137 } 138 139 static inline int pte_young(pte_t pte) 140 { 141 return pte_get_bits(pte, _PAGE_ACCESSED); 142 } 143 144 static inline int pte_newpage(pte_t pte) 145 { 146 return pte_get_bits(pte, _PAGE_NEWPAGE); 147 } 148 149 static inline int pte_newprot(pte_t pte) 150 { 151 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT))); 152 } 153 154 /* 155 * ================================= 156 * Flags setting section. 157 * ================================= 158 */ 159 160 static inline pte_t pte_mknewprot(pte_t pte) 161 { 162 pte_set_bits(pte, _PAGE_NEWPROT); 163 return(pte); 164 } 165 166 static inline pte_t pte_mkclean(pte_t pte) 167 { 168 pte_clear_bits(pte, _PAGE_DIRTY); 169 return(pte); 170 } 171 172 static inline pte_t pte_mkold(pte_t pte) 173 { 174 pte_clear_bits(pte, _PAGE_ACCESSED); 175 return(pte); 176 } 177 178 static inline pte_t pte_wrprotect(pte_t pte) 179 { 180 if (likely(pte_get_bits(pte, _PAGE_RW))) 181 pte_clear_bits(pte, _PAGE_RW); 182 else 183 return pte; 184 return(pte_mknewprot(pte)); 185 } 186 187 static inline pte_t pte_mkread(pte_t pte) 188 { 189 if (unlikely(pte_get_bits(pte, _PAGE_USER))) 190 return pte; 191 pte_set_bits(pte, _PAGE_USER); 192 return(pte_mknewprot(pte)); 193 } 194 195 static inline pte_t pte_mkdirty(pte_t pte) 196 { 197 pte_set_bits(pte, _PAGE_DIRTY); 198 return(pte); 199 } 200 201 static inline pte_t pte_mkyoung(pte_t pte) 202 { 203 pte_set_bits(pte, _PAGE_ACCESSED); 204 return(pte); 205 } 206 207 static inline pte_t pte_mkwrite(pte_t pte) 208 { 209 if (unlikely(pte_get_bits(pte, _PAGE_RW))) 210 return pte; 211 pte_set_bits(pte, _PAGE_RW); 212 return(pte_mknewprot(pte)); 213 } 214 215 static inline pte_t pte_mkuptodate(pte_t pte) 216 { 217 pte_clear_bits(pte, _PAGE_NEWPAGE); 218 if(pte_present(pte)) 219 pte_clear_bits(pte, _PAGE_NEWPROT); 220 return(pte); 221 } 222 223 static inline pte_t pte_mknewpage(pte_t pte) 224 { 225 pte_set_bits(pte, _PAGE_NEWPAGE); 226 return(pte); 227 } 228 229 static inline void set_pte(pte_t *pteptr, pte_t pteval) 230 { 231 pte_copy(*pteptr, pteval); 232 233 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so 234 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to 235 * mapped pages. 236 */ 237 238 *pteptr = pte_mknewpage(*pteptr); 239 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr); 240 } 241 242 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 243 pte_t *pteptr, pte_t pteval) 244 { 245 set_pte(pteptr, pteval); 246 } 247 248 #define __HAVE_ARCH_PTE_SAME 249 static inline int pte_same(pte_t pte_a, pte_t pte_b) 250 { 251 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE); 252 } 253 254 /* 255 * Conversion functions: convert a page and protection to a page entry, 256 * and a page entry and page directory to the page they refer to. 257 */ 258 259 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys)) 260 #define __virt_to_page(virt) phys_to_page(__pa(virt)) 261 #define page_to_phys(page) pfn_to_phys(page_to_pfn(page)) 262 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr) 263 264 #define mk_pte(page, pgprot) \ 265 ({ pte_t pte; \ 266 \ 267 pte_set_val(pte, page_to_phys(page), (pgprot)); \ 268 if (pte_present(pte)) \ 269 pte_mknewprot(pte_mknewpage(pte)); \ 270 pte;}) 271 272 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 273 { 274 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot); 275 return pte; 276 } 277 278 /* 279 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD] 280 * 281 * this macro returns the index of the entry in the pmd page which would 282 * control the given virtual address 283 */ 284 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) 285 286 struct mm_struct; 287 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr); 288 289 #define update_mmu_cache(vma,address,ptep) do {} while (0) 290 291 /* Encode and de-code a swap entry */ 292 #define __swp_type(x) (((x).val >> 5) & 0x1f) 293 #define __swp_offset(x) ((x).val >> 11) 294 295 #define __swp_entry(type, offset) \ 296 ((swp_entry_t) { ((type) << 5) | ((offset) << 11) }) 297 #define __pte_to_swp_entry(pte) \ 298 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) }) 299 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 300 301 /* Clear a kernel PTE and flush it from the TLB */ 302 #define kpte_clear_flush(ptep, vaddr) \ 303 do { \ 304 pte_clear(&init_mm, (vaddr), (ptep)); \ 305 __flush_tlb_one((vaddr)); \ 306 } while (0) 307 308 #endif 309