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 #ifdef CONFIG_3_LEVEL_PGTABLES 28 #include <asm/pgtable-3level.h> 29 #else 30 #include <asm/pgtable-2level.h> 31 #endif 32 33 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 34 35 /* zero page used for uninitialized stuff */ 36 extern unsigned long *empty_zero_page; 37 38 /* Just any arbitrary offset to the start of the vmalloc VM area: the 39 * current 8MB value just means that there will be a 8MB "hole" after the 40 * physical memory until the kernel virtual memory starts. That means that 41 * any out-of-bounds memory accesses will hopefully be caught. 42 * The vmalloc() routines leaves a hole of 4kB between each vmalloced 43 * area for the same reason. ;) 44 */ 45 46 extern unsigned long end_iomem; 47 48 #define VMALLOC_OFFSET (__va_space) 49 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 50 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK) 51 #define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE) 52 #define MODULES_VADDR VMALLOC_START 53 #define MODULES_END VMALLOC_END 54 #define MODULES_LEN (MODULES_VADDR - MODULES_END) 55 56 #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY) 57 #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) 58 #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) 59 #define __PAGE_KERNEL_EXEC \ 60 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 61 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED) 62 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED) 63 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 64 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) 65 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) 66 #define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC) 67 68 /* 69 * The i386 can't do page protection for execute, and considers that the same 70 * are read. 71 * Also, write permissions imply read permissions. This is the closest we can 72 * get.. 73 */ 74 75 /* 76 * ZERO_PAGE is a global shared page that is always zero: used 77 * for zero-mapped memory areas etc.. 78 */ 79 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page) 80 81 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE)) 82 83 #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE)) 84 #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE) 85 86 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT) 87 #define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0) 88 89 #define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE) 90 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE) 91 92 #define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE) 93 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE) 94 95 #define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE) 96 #define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE) 97 98 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) 99 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK) 100 101 #define pte_page(x) pfn_to_page(pte_pfn(x)) 102 103 #define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE)) 104 105 /* 106 * ================================= 107 * Flags checking section. 108 * ================================= 109 */ 110 111 static inline int pte_none(pte_t pte) 112 { 113 return pte_is_zero(pte); 114 } 115 116 /* 117 * The following only work if pte_present() is true. 118 * Undefined behaviour if not.. 119 */ 120 static inline int pte_read(pte_t pte) 121 { 122 return((pte_get_bits(pte, _PAGE_USER)) && 123 !(pte_get_bits(pte, _PAGE_PROTNONE))); 124 } 125 126 static inline int pte_exec(pte_t pte){ 127 return((pte_get_bits(pte, _PAGE_USER)) && 128 !(pte_get_bits(pte, _PAGE_PROTNONE))); 129 } 130 131 static inline int pte_write(pte_t pte) 132 { 133 return((pte_get_bits(pte, _PAGE_RW)) && 134 !(pte_get_bits(pte, _PAGE_PROTNONE))); 135 } 136 137 static inline int pte_dirty(pte_t pte) 138 { 139 return pte_get_bits(pte, _PAGE_DIRTY); 140 } 141 142 static inline int pte_young(pte_t pte) 143 { 144 return pte_get_bits(pte, _PAGE_ACCESSED); 145 } 146 147 static inline int pte_newpage(pte_t pte) 148 { 149 return pte_get_bits(pte, _PAGE_NEWPAGE); 150 } 151 152 static inline int pte_newprot(pte_t pte) 153 { 154 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT))); 155 } 156 157 /* 158 * ================================= 159 * Flags setting section. 160 * ================================= 161 */ 162 163 static inline pte_t pte_mknewprot(pte_t pte) 164 { 165 pte_set_bits(pte, _PAGE_NEWPROT); 166 return(pte); 167 } 168 169 static inline pte_t pte_mkclean(pte_t pte) 170 { 171 pte_clear_bits(pte, _PAGE_DIRTY); 172 return(pte); 173 } 174 175 static inline pte_t pte_mkold(pte_t pte) 176 { 177 pte_clear_bits(pte, _PAGE_ACCESSED); 178 return(pte); 179 } 180 181 static inline pte_t pte_wrprotect(pte_t pte) 182 { 183 if (likely(pte_get_bits(pte, _PAGE_RW))) 184 pte_clear_bits(pte, _PAGE_RW); 185 else 186 return pte; 187 return(pte_mknewprot(pte)); 188 } 189 190 static inline pte_t pte_mkread(pte_t pte) 191 { 192 if (unlikely(pte_get_bits(pte, _PAGE_USER))) 193 return pte; 194 pte_set_bits(pte, _PAGE_USER); 195 return(pte_mknewprot(pte)); 196 } 197 198 static inline pte_t pte_mkdirty(pte_t pte) 199 { 200 pte_set_bits(pte, _PAGE_DIRTY); 201 return(pte); 202 } 203 204 static inline pte_t pte_mkyoung(pte_t pte) 205 { 206 pte_set_bits(pte, _PAGE_ACCESSED); 207 return(pte); 208 } 209 210 static inline pte_t pte_mkwrite(pte_t pte) 211 { 212 if (unlikely(pte_get_bits(pte, _PAGE_RW))) 213 return pte; 214 pte_set_bits(pte, _PAGE_RW); 215 return(pte_mknewprot(pte)); 216 } 217 218 static inline pte_t pte_mkuptodate(pte_t pte) 219 { 220 pte_clear_bits(pte, _PAGE_NEWPAGE); 221 if(pte_present(pte)) 222 pte_clear_bits(pte, _PAGE_NEWPROT); 223 return(pte); 224 } 225 226 static inline pte_t pte_mknewpage(pte_t pte) 227 { 228 pte_set_bits(pte, _PAGE_NEWPAGE); 229 return(pte); 230 } 231 232 static inline void set_pte(pte_t *pteptr, pte_t pteval) 233 { 234 pte_copy(*pteptr, pteval); 235 236 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so 237 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to 238 * mapped pages. 239 */ 240 241 *pteptr = pte_mknewpage(*pteptr); 242 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr); 243 } 244 245 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 246 pte_t *pteptr, pte_t pteval) 247 { 248 set_pte(pteptr, pteval); 249 } 250 251 #define __HAVE_ARCH_PTE_SAME 252 static inline int pte_same(pte_t pte_a, pte_t pte_b) 253 { 254 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE); 255 } 256 257 /* 258 * Conversion functions: convert a page and protection to a page entry, 259 * and a page entry and page directory to the page they refer to. 260 */ 261 262 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys)) 263 #define __virt_to_page(virt) phys_to_page(__pa(virt)) 264 #define page_to_phys(page) pfn_to_phys(page_to_pfn(page)) 265 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr) 266 267 #define mk_pte(page, pgprot) \ 268 ({ pte_t pte; \ 269 \ 270 pte_set_val(pte, page_to_phys(page), (pgprot)); \ 271 if (pte_present(pte)) \ 272 pte_mknewprot(pte_mknewpage(pte)); \ 273 pte;}) 274 275 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 276 { 277 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot); 278 return pte; 279 } 280 281 /* 282 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD] 283 * 284 * this macro returns the index of the entry in the pmd page which would 285 * control the given virtual address 286 */ 287 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) 288 289 struct mm_struct; 290 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr); 291 292 #define update_mmu_cache(vma,address,ptep) do {} while (0) 293 294 /* 295 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that 296 * are !pte_none() && !pte_present(). 297 * 298 * Format of swap PTEs: 299 * 300 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 301 * 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 0 302 * <--------------- offset ----------------> E < type -> 0 0 0 1 0 303 * 304 * E is the exclusive marker that is not stored in swap entries. 305 * _PAGE_NEWPAGE (bit 1) is always set to 1 in set_pte(). 306 */ 307 #define __swp_type(x) (((x).val >> 5) & 0x1f) 308 #define __swp_offset(x) ((x).val >> 11) 309 310 #define __swp_entry(type, offset) \ 311 ((swp_entry_t) { (((type) & 0x1f) << 5) | ((offset) << 11) }) 312 #define __pte_to_swp_entry(pte) \ 313 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) }) 314 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 315 316 static inline int pte_swp_exclusive(pte_t pte) 317 { 318 return pte_get_bits(pte, _PAGE_SWP_EXCLUSIVE); 319 } 320 321 static inline pte_t pte_swp_mkexclusive(pte_t pte) 322 { 323 pte_set_bits(pte, _PAGE_SWP_EXCLUSIVE); 324 return pte; 325 } 326 327 static inline pte_t pte_swp_clear_exclusive(pte_t pte) 328 { 329 pte_clear_bits(pte, _PAGE_SWP_EXCLUSIVE); 330 return pte; 331 } 332 333 /* Clear a kernel PTE and flush it from the TLB */ 334 #define kpte_clear_flush(ptep, vaddr) \ 335 do { \ 336 pte_clear(&init_mm, (vaddr), (ptep)); \ 337 __flush_tlb_one((vaddr)); \ 338 } while (0) 339 340 #endif 341