1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_PGTABLE_64_H 3 #define _ASM_X86_PGTABLE_64_H 4 5 #include <linux/const.h> 6 #include <asm/pgtable_64_types.h> 7 8 #ifndef __ASSEMBLY__ 9 10 /* 11 * This file contains the functions and defines necessary to modify and use 12 * the x86-64 page table tree. 13 */ 14 #include <asm/processor.h> 15 #include <linux/bitops.h> 16 #include <linux/threads.h> 17 #include <asm/fixmap.h> 18 19 extern p4d_t level4_kernel_pgt[512]; 20 extern p4d_t level4_ident_pgt[512]; 21 extern pud_t level3_kernel_pgt[512]; 22 extern pud_t level3_ident_pgt[512]; 23 extern pmd_t level2_kernel_pgt[512]; 24 extern pmd_t level2_fixmap_pgt[512]; 25 extern pmd_t level2_ident_pgt[512]; 26 extern pte_t level1_fixmap_pgt[512 * FIXMAP_PMD_NUM]; 27 extern pgd_t init_top_pgt[]; 28 29 #define swapper_pg_dir init_top_pgt 30 31 extern void paging_init(void); 32 static inline void sync_initial_page_table(void) { } 33 34 #define pte_ERROR(e) \ 35 pr_err("%s:%d: bad pte %p(%016lx)\n", \ 36 __FILE__, __LINE__, &(e), pte_val(e)) 37 #define pmd_ERROR(e) \ 38 pr_err("%s:%d: bad pmd %p(%016lx)\n", \ 39 __FILE__, __LINE__, &(e), pmd_val(e)) 40 #define pud_ERROR(e) \ 41 pr_err("%s:%d: bad pud %p(%016lx)\n", \ 42 __FILE__, __LINE__, &(e), pud_val(e)) 43 44 #if CONFIG_PGTABLE_LEVELS >= 5 45 #define p4d_ERROR(e) \ 46 pr_err("%s:%d: bad p4d %p(%016lx)\n", \ 47 __FILE__, __LINE__, &(e), p4d_val(e)) 48 #endif 49 50 #define pgd_ERROR(e) \ 51 pr_err("%s:%d: bad pgd %p(%016lx)\n", \ 52 __FILE__, __LINE__, &(e), pgd_val(e)) 53 54 struct mm_struct; 55 56 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte); 57 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte); 58 59 static inline void native_set_pte(pte_t *ptep, pte_t pte) 60 { 61 WRITE_ONCE(*ptep, pte); 62 } 63 64 static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr, 65 pte_t *ptep) 66 { 67 native_set_pte(ptep, native_make_pte(0)); 68 } 69 70 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte) 71 { 72 native_set_pte(ptep, pte); 73 } 74 75 static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd) 76 { 77 WRITE_ONCE(*pmdp, pmd); 78 } 79 80 static inline void native_pmd_clear(pmd_t *pmd) 81 { 82 native_set_pmd(pmd, native_make_pmd(0)); 83 } 84 85 static inline pte_t native_ptep_get_and_clear(pte_t *xp) 86 { 87 #ifdef CONFIG_SMP 88 return native_make_pte(xchg(&xp->pte, 0)); 89 #else 90 /* native_local_ptep_get_and_clear, 91 but duplicated because of cyclic dependency */ 92 pte_t ret = *xp; 93 native_pte_clear(NULL, 0, xp); 94 return ret; 95 #endif 96 } 97 98 static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp) 99 { 100 #ifdef CONFIG_SMP 101 return native_make_pmd(xchg(&xp->pmd, 0)); 102 #else 103 /* native_local_pmdp_get_and_clear, 104 but duplicated because of cyclic dependency */ 105 pmd_t ret = *xp; 106 native_pmd_clear(xp); 107 return ret; 108 #endif 109 } 110 111 static inline void native_set_pud(pud_t *pudp, pud_t pud) 112 { 113 WRITE_ONCE(*pudp, pud); 114 } 115 116 static inline void native_pud_clear(pud_t *pud) 117 { 118 native_set_pud(pud, native_make_pud(0)); 119 } 120 121 static inline pud_t native_pudp_get_and_clear(pud_t *xp) 122 { 123 #ifdef CONFIG_SMP 124 return native_make_pud(xchg(&xp->pud, 0)); 125 #else 126 /* native_local_pudp_get_and_clear, 127 * but duplicated because of cyclic dependency 128 */ 129 pud_t ret = *xp; 130 131 native_pud_clear(xp); 132 return ret; 133 #endif 134 } 135 136 static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d) 137 { 138 pgd_t pgd; 139 140 if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) { 141 WRITE_ONCE(*p4dp, p4d); 142 return; 143 } 144 145 pgd = native_make_pgd(native_p4d_val(p4d)); 146 pgd = pti_set_user_pgtbl((pgd_t *)p4dp, pgd); 147 WRITE_ONCE(*p4dp, native_make_p4d(native_pgd_val(pgd))); 148 } 149 150 static inline void native_p4d_clear(p4d_t *p4d) 151 { 152 native_set_p4d(p4d, native_make_p4d(0)); 153 } 154 155 static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd) 156 { 157 WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd)); 158 } 159 160 static inline void native_pgd_clear(pgd_t *pgd) 161 { 162 native_set_pgd(pgd, native_make_pgd(0)); 163 } 164 165 extern void sync_global_pgds(unsigned long start, unsigned long end); 166 167 /* 168 * Conversion functions: convert a page and protection to a page entry, 169 * and a page entry and page directory to the page they refer to. 170 */ 171 172 /* 173 * Level 4 access. 174 */ 175 #define mk_kernel_pgd(address) __pgd((address) | _KERNPG_TABLE) 176 177 /* PUD - Level3 access */ 178 179 /* PMD - Level 2 access */ 180 181 /* PTE - Level 1 access. */ 182 183 /* x86-64 always has all page tables mapped. */ 184 #define pte_offset_map(dir, address) pte_offset_kernel((dir), (address)) 185 #define pte_unmap(pte) ((void)(pte))/* NOP */ 186 187 /* 188 * Encode and de-code a swap entry 189 * 190 * | ... | 11| 10| 9|8|7|6|5| 4| 3|2| 1|0| <- bit number 191 * | ... |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names 192 * | TYPE (59-63) | ~OFFSET (9-58) |0|0|X|X| X| X|F|SD|0| <- swp entry 193 * 194 * G (8) is aliased and used as a PROT_NONE indicator for 195 * !present ptes. We need to start storing swap entries above 196 * there. We also need to avoid using A and D because of an 197 * erratum where they can be incorrectly set by hardware on 198 * non-present PTEs. 199 * 200 * SD Bits 1-4 are not used in non-present format and available for 201 * special use described below: 202 * 203 * SD (1) in swp entry is used to store soft dirty bit, which helps us 204 * remember soft dirty over page migration 205 * 206 * F (2) in swp entry is used to record when a pagetable is 207 * writeprotected by userfaultfd WP support. 208 * 209 * Bit 7 in swp entry should be 0 because pmd_present checks not only P, 210 * but also L and G. 211 * 212 * The offset is inverted by a binary not operation to make the high 213 * physical bits set. 214 */ 215 #define SWP_TYPE_BITS 5 216 217 #define SWP_OFFSET_FIRST_BIT (_PAGE_BIT_PROTNONE + 1) 218 219 /* We always extract/encode the offset by shifting it all the way up, and then down again */ 220 #define SWP_OFFSET_SHIFT (SWP_OFFSET_FIRST_BIT+SWP_TYPE_BITS) 221 222 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS) 223 224 /* Extract the high bits for type */ 225 #define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS)) 226 227 /* Shift up (to get rid of type), then down to get value */ 228 #define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT) 229 230 /* 231 * Shift the offset up "too far" by TYPE bits, then down again 232 * The offset is inverted by a binary not operation to make the high 233 * physical bits set. 234 */ 235 #define __swp_entry(type, offset) ((swp_entry_t) { \ 236 (~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \ 237 | ((unsigned long)(type) << (64-SWP_TYPE_BITS)) }) 238 239 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val((pte)) }) 240 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val((pmd)) }) 241 #define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val }) 242 #define __swp_entry_to_pmd(x) ((pmd_t) { .pmd = (x).val }) 243 244 extern int kern_addr_valid(unsigned long addr); 245 extern void cleanup_highmap(void); 246 247 #define HAVE_ARCH_UNMAPPED_AREA 248 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN 249 250 #define PAGE_AGP PAGE_KERNEL_NOCACHE 251 #define HAVE_PAGE_AGP 1 252 253 /* fs/proc/kcore.c */ 254 #define kc_vaddr_to_offset(v) ((v) & __VIRTUAL_MASK) 255 #define kc_offset_to_vaddr(o) ((o) | ~__VIRTUAL_MASK) 256 257 #define __HAVE_ARCH_PTE_SAME 258 259 #define vmemmap ((struct page *)VMEMMAP_START) 260 261 extern void init_extra_mapping_uc(unsigned long phys, unsigned long size); 262 extern void init_extra_mapping_wb(unsigned long phys, unsigned long size); 263 264 #define gup_fast_permitted gup_fast_permitted 265 static inline bool gup_fast_permitted(unsigned long start, unsigned long end) 266 { 267 if (end >> __VIRTUAL_MASK_SHIFT) 268 return false; 269 return true; 270 } 271 272 #include <asm/pgtable-invert.h> 273 274 #endif /* !__ASSEMBLY__ */ 275 #endif /* _ASM_X86_PGTABLE_64_H */ 276