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 /* We borrow bit 10 to store the exclusive marker in swap PTEs. */ 25 #define _PAGE_SWP_EXCLUSIVE 0x400 26 27 #if CONFIG_PGTABLE_LEVELS == 4 28 #include <asm/pgtable-4level.h> 29 #elif CONFIG_PGTABLE_LEVELS == 2 30 #include <asm/pgtable-2level.h> 31 #else 32 #error "Unsupported number of page table levels" 33 #endif 34 35 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 36 37 /* zero page used for uninitialized stuff */ 38 extern unsigned long *empty_zero_page; 39 40 /* Just any arbitrary offset to the start of the vmalloc VM area: the 41 * current 8MB value just means that there will be a 8MB "hole" after the 42 * physical memory until the kernel virtual memory starts. That means that 43 * any out-of-bounds memory accesses will hopefully be caught. 44 * The vmalloc() routines leaves a hole of 4kB between each vmalloced 45 * area for the same reason. ;) 46 */ 47 48 extern unsigned long end_iomem; 49 50 #define VMALLOC_OFFSET (__va_space) 51 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 52 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK) 53 #define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE) 54 #define MODULES_VADDR VMALLOC_START 55 #define MODULES_END VMALLOC_END 56 #define MODULES_LEN (MODULES_VADDR - MODULES_END) 57 58 #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY) 59 #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) 60 #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) 61 #define __PAGE_KERNEL_EXEC \ 62 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 63 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED) 64 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED) 65 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 66 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 67 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 68 #define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC) 69 70 /* 71 * The i386 can't do page protection for execute, and considers that the same 72 * are read. 73 * Also, write permissions imply read permissions. This is the closest we can 74 * get.. 75 */ 76 77 /* 78 * ZERO_PAGE is a global shared page that is always zero: used 79 * for zero-mapped memory areas etc.. 80 */ 81 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page) 82 83 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE)) 84 85 #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE)) 86 #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE) 87 88 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT) 89 #define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0) 90 91 #define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE) 92 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE) 93 94 #define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE) 95 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE) 96 97 #define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE) 98 #define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE) 99 100 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) 101 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK) 102 103 #define pte_page(x) pfn_to_page(pte_pfn(x)) 104 105 #define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE)) 106 107 /* 108 * ================================= 109 * Flags checking section. 110 * ================================= 111 */ 112 113 static inline int pte_none(pte_t pte) 114 { 115 return pte_is_zero(pte); 116 } 117 118 /* 119 * The following only work if pte_present() is true. 120 * Undefined behaviour if not.. 121 */ 122 static inline int pte_read(pte_t pte) 123 { 124 return((pte_get_bits(pte, _PAGE_USER)) && 125 !(pte_get_bits(pte, _PAGE_PROTNONE))); 126 } 127 128 static inline int pte_exec(pte_t pte){ 129 return((pte_get_bits(pte, _PAGE_USER)) && 130 !(pte_get_bits(pte, _PAGE_PROTNONE))); 131 } 132 133 static inline int pte_write(pte_t pte) 134 { 135 return((pte_get_bits(pte, _PAGE_RW)) && 136 !(pte_get_bits(pte, _PAGE_PROTNONE))); 137 } 138 139 static inline int pte_dirty(pte_t pte) 140 { 141 return pte_get_bits(pte, _PAGE_DIRTY); 142 } 143 144 static inline int pte_young(pte_t pte) 145 { 146 return pte_get_bits(pte, _PAGE_ACCESSED); 147 } 148 149 static inline int pte_newpage(pte_t pte) 150 { 151 return pte_get_bits(pte, _PAGE_NEWPAGE); 152 } 153 154 static inline int pte_newprot(pte_t pte) 155 { 156 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT))); 157 } 158 159 /* 160 * ================================= 161 * Flags setting section. 162 * ================================= 163 */ 164 165 static inline pte_t pte_mknewprot(pte_t pte) 166 { 167 pte_set_bits(pte, _PAGE_NEWPROT); 168 return(pte); 169 } 170 171 static inline pte_t pte_mkclean(pte_t pte) 172 { 173 pte_clear_bits(pte, _PAGE_DIRTY); 174 return(pte); 175 } 176 177 static inline pte_t pte_mkold(pte_t pte) 178 { 179 pte_clear_bits(pte, _PAGE_ACCESSED); 180 return(pte); 181 } 182 183 static inline pte_t pte_wrprotect(pte_t pte) 184 { 185 if (likely(pte_get_bits(pte, _PAGE_RW))) 186 pte_clear_bits(pte, _PAGE_RW); 187 else 188 return pte; 189 return(pte_mknewprot(pte)); 190 } 191 192 static inline pte_t pte_mkread(pte_t pte) 193 { 194 if (unlikely(pte_get_bits(pte, _PAGE_USER))) 195 return pte; 196 pte_set_bits(pte, _PAGE_USER); 197 return(pte_mknewprot(pte)); 198 } 199 200 static inline pte_t pte_mkdirty(pte_t pte) 201 { 202 pte_set_bits(pte, _PAGE_DIRTY); 203 return(pte); 204 } 205 206 static inline pte_t pte_mkyoung(pte_t pte) 207 { 208 pte_set_bits(pte, _PAGE_ACCESSED); 209 return(pte); 210 } 211 212 static inline pte_t pte_mkwrite_novma(pte_t pte) 213 { 214 if (unlikely(pte_get_bits(pte, _PAGE_RW))) 215 return pte; 216 pte_set_bits(pte, _PAGE_RW); 217 return(pte_mknewprot(pte)); 218 } 219 220 static inline pte_t pte_mkuptodate(pte_t pte) 221 { 222 pte_clear_bits(pte, _PAGE_NEWPAGE); 223 if(pte_present(pte)) 224 pte_clear_bits(pte, _PAGE_NEWPROT); 225 return(pte); 226 } 227 228 static inline pte_t pte_mknewpage(pte_t pte) 229 { 230 pte_set_bits(pte, _PAGE_NEWPAGE); 231 return(pte); 232 } 233 234 static inline void set_pte(pte_t *pteptr, pte_t pteval) 235 { 236 pte_copy(*pteptr, pteval); 237 238 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so 239 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to 240 * mapped pages. 241 */ 242 243 *pteptr = pte_mknewpage(*pteptr); 244 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr); 245 } 246 247 #define PFN_PTE_SHIFT PAGE_SHIFT 248 249 static inline void um_tlb_mark_sync(struct mm_struct *mm, unsigned long start, 250 unsigned long end) 251 { 252 if (!mm->context.sync_tlb_range_to) { 253 mm->context.sync_tlb_range_from = start; 254 mm->context.sync_tlb_range_to = end; 255 } else { 256 if (start < mm->context.sync_tlb_range_from) 257 mm->context.sync_tlb_range_from = start; 258 if (end > mm->context.sync_tlb_range_to) 259 mm->context.sync_tlb_range_to = end; 260 } 261 } 262 263 #define set_ptes set_ptes 264 static inline void set_ptes(struct mm_struct *mm, unsigned long addr, 265 pte_t *ptep, pte_t pte, int nr) 266 { 267 /* Basically the default implementation */ 268 size_t length = nr * PAGE_SIZE; 269 270 for (;;) { 271 set_pte(ptep, pte); 272 if (--nr == 0) 273 break; 274 ptep++; 275 pte = __pte(pte_val(pte) + (nr << PFN_PTE_SHIFT)); 276 } 277 278 um_tlb_mark_sync(mm, addr, addr + length); 279 } 280 281 #define __HAVE_ARCH_PTE_SAME 282 static inline int pte_same(pte_t pte_a, pte_t pte_b) 283 { 284 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE); 285 } 286 287 /* 288 * Conversion functions: convert a page and protection to a page entry, 289 * and a page entry and page directory to the page they refer to. 290 */ 291 292 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys)) 293 #define __virt_to_page(virt) phys_to_page(__pa(virt)) 294 #define page_to_phys(page) pfn_to_phys(page_to_pfn(page)) 295 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr) 296 297 #define mk_pte(page, pgprot) \ 298 ({ pte_t pte; \ 299 \ 300 pte_set_val(pte, page_to_phys(page), (pgprot)); \ 301 if (pte_present(pte)) \ 302 pte_mknewprot(pte_mknewpage(pte)); \ 303 pte;}) 304 305 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 306 { 307 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot); 308 return pte; 309 } 310 311 /* 312 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD] 313 * 314 * this macro returns the index of the entry in the pmd page which would 315 * control the given virtual address 316 */ 317 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) 318 319 struct mm_struct; 320 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr); 321 322 #define update_mmu_cache(vma,address,ptep) do {} while (0) 323 #define update_mmu_cache_range(vmf, vma, address, ptep, nr) do {} while (0) 324 325 /* 326 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that 327 * are !pte_none() && !pte_present(). 328 * 329 * Format of swap PTEs: 330 * 331 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 332 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 333 * <--------------- offset ----------------> E < type -> 0 0 0 1 0 334 * 335 * E is the exclusive marker that is not stored in swap entries. 336 * _PAGE_NEWPAGE (bit 1) is always set to 1 in set_pte(). 337 */ 338 #define __swp_type(x) (((x).val >> 5) & 0x1f) 339 #define __swp_offset(x) ((x).val >> 11) 340 341 #define __swp_entry(type, offset) \ 342 ((swp_entry_t) { (((type) & 0x1f) << 5) | ((offset) << 11) }) 343 #define __pte_to_swp_entry(pte) \ 344 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) }) 345 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 346 347 static inline int pte_swp_exclusive(pte_t pte) 348 { 349 return pte_get_bits(pte, _PAGE_SWP_EXCLUSIVE); 350 } 351 352 static inline pte_t pte_swp_mkexclusive(pte_t pte) 353 { 354 pte_set_bits(pte, _PAGE_SWP_EXCLUSIVE); 355 return pte; 356 } 357 358 static inline pte_t pte_swp_clear_exclusive(pte_t pte) 359 { 360 pte_clear_bits(pte, _PAGE_SWP_EXCLUSIVE); 361 return pte; 362 } 363 364 #endif 365