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/page.h> 12 #include <linux/mm_types.h> 13 14 #define _PAGE_PRESENT 0x001 15 #define _PAGE_NEEDSYNC 0x002 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 #ifndef COMPILE_OFFSETS 49 #include <as-layout.h> /* for high_physmem */ 50 #endif 51 52 #define VMALLOC_OFFSET (__va_space) 53 #define VMALLOC_START ((high_physmem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 54 #define VMALLOC_END (TASK_SIZE-2*PAGE_SIZE) 55 #define MODULES_VADDR VMALLOC_START 56 #define MODULES_END VMALLOC_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_NEEDSYNC)) 84 85 #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEEDSYNC)) 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_NEEDSYNC; } while (0) 90 91 #define pmd_needsync(x) (pmd_val(x) & _PAGE_NEEDSYNC) 92 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEEDSYNC) 93 94 #define pud_needsync(x) (pud_val(x) & _PAGE_NEEDSYNC) 95 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEEDSYNC) 96 97 #define p4d_needsync(x) (p4d_val(x) & _PAGE_NEEDSYNC) 98 #define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEEDSYNC) 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_needsync(pte_t pte) 150 { 151 return pte_get_bits(pte, _PAGE_NEEDSYNC); 152 } 153 154 /* 155 * ================================= 156 * Flags setting section. 157 * ================================= 158 */ 159 160 static inline pte_t pte_mkclean(pte_t pte) 161 { 162 pte_clear_bits(pte, _PAGE_DIRTY); 163 return(pte); 164 } 165 166 static inline pte_t pte_mkold(pte_t pte) 167 { 168 pte_clear_bits(pte, _PAGE_ACCESSED); 169 return(pte); 170 } 171 172 static inline pte_t pte_wrprotect(pte_t pte) 173 { 174 pte_clear_bits(pte, _PAGE_RW); 175 return pte; 176 } 177 178 static inline pte_t pte_mkread(pte_t pte) 179 { 180 pte_set_bits(pte, _PAGE_USER); 181 return pte; 182 } 183 184 static inline pte_t pte_mkdirty(pte_t pte) 185 { 186 pte_set_bits(pte, _PAGE_DIRTY); 187 return(pte); 188 } 189 190 static inline pte_t pte_mkyoung(pte_t pte) 191 { 192 pte_set_bits(pte, _PAGE_ACCESSED); 193 return(pte); 194 } 195 196 static inline pte_t pte_mkwrite_novma(pte_t pte) 197 { 198 pte_set_bits(pte, _PAGE_RW); 199 return pte; 200 } 201 202 static inline pte_t pte_mkuptodate(pte_t pte) 203 { 204 pte_clear_bits(pte, _PAGE_NEEDSYNC); 205 return pte; 206 } 207 208 static inline pte_t pte_mkneedsync(pte_t pte) 209 { 210 pte_set_bits(pte, _PAGE_NEEDSYNC); 211 return(pte); 212 } 213 214 static inline void set_pte(pte_t *pteptr, pte_t pteval) 215 { 216 pte_copy(*pteptr, pteval); 217 218 /* If it's a swap entry, it needs to be marked _PAGE_NEEDSYNC so 219 * update_pte_range knows to unmap it. 220 */ 221 222 *pteptr = pte_mkneedsync(*pteptr); 223 } 224 225 #define PFN_PTE_SHIFT PAGE_SHIFT 226 227 static inline void um_tlb_mark_sync(struct mm_struct *mm, unsigned long start, 228 unsigned long end) 229 { 230 guard(spinlock_irqsave)(&mm->context.sync_tlb_lock); 231 232 if (!mm->context.sync_tlb_range_to) { 233 mm->context.sync_tlb_range_from = start; 234 mm->context.sync_tlb_range_to = end; 235 } else { 236 if (start < mm->context.sync_tlb_range_from) 237 mm->context.sync_tlb_range_from = start; 238 if (end > mm->context.sync_tlb_range_to) 239 mm->context.sync_tlb_range_to = end; 240 } 241 } 242 243 #define set_ptes set_ptes 244 static inline void set_ptes(struct mm_struct *mm, unsigned long addr, 245 pte_t *ptep, pte_t pte, int nr) 246 { 247 /* Basically the default implementation */ 248 size_t length = nr * PAGE_SIZE; 249 250 for (;;) { 251 set_pte(ptep, pte); 252 if (--nr == 0) 253 break; 254 ptep++; 255 pte = __pte(pte_val(pte) + (nr << PFN_PTE_SHIFT)); 256 } 257 258 um_tlb_mark_sync(mm, addr, addr + length); 259 } 260 261 #define __HAVE_ARCH_PTE_SAME 262 static inline int pte_same(pte_t pte_a, pte_t pte_b) 263 { 264 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEEDSYNC); 265 } 266 267 #define __virt_to_page(virt) phys_to_page(__pa(virt)) 268 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr) 269 270 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) 271 { 272 pte_t pte; 273 274 pte_set_val(pte, pfn_to_phys(pfn), pgprot); 275 276 return pte; 277 } 278 279 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 280 { 281 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot); 282 return pte; 283 } 284 285 /* 286 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD] 287 * 288 * this macro returns the index of the entry in the pmd page which would 289 * control the given virtual address 290 */ 291 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) 292 293 struct mm_struct; 294 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr); 295 296 #define update_mmu_cache(vma,address,ptep) do {} while (0) 297 #define update_mmu_cache_range(vmf, vma, address, ptep, nr) do {} while (0) 298 299 /* 300 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that 301 * are !pte_none() && !pte_present(). 302 * 303 * Format of swap PTEs: 304 * 305 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 306 * 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 0 307 * <--------------- offset ----------------> E < type -> 0 0 0 1 0 308 * 309 * E is the exclusive marker that is not stored in swap entries. 310 * _PAGE_NEEDSYNC (bit 1) is always set to 1 in set_pte(). 311 */ 312 #define __swp_type(x) (((x).val >> 5) & 0x1f) 313 #define __swp_offset(x) ((x).val >> 11) 314 315 #define __swp_entry(type, offset) \ 316 ((swp_entry_t) { (((type) & 0x1f) << 5) | ((offset) << 11) }) 317 #define __pte_to_swp_entry(pte) \ 318 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) }) 319 #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 320 321 static inline bool pte_swp_exclusive(pte_t pte) 322 { 323 return pte_get_bits(pte, _PAGE_SWP_EXCLUSIVE); 324 } 325 326 static inline pte_t pte_swp_mkexclusive(pte_t pte) 327 { 328 pte_set_bits(pte, _PAGE_SWP_EXCLUSIVE); 329 return pte; 330 } 331 332 static inline pte_t pte_swp_clear_exclusive(pte_t pte) 333 { 334 pte_clear_bits(pte, _PAGE_SWP_EXCLUSIVE); 335 return pte; 336 } 337 338 #endif 339