arch/x86/include/asm/pgtable_64.h

   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
  18 extern p4d_t level4_kernel_pgt[512];
  19 extern p4d_t level4_ident_pgt[512];
  20 extern pud_t level3_kernel_pgt[512];
  21 extern pud_t level3_ident_pgt[512];
  22 extern pmd_t level2_kernel_pgt[512];
  23 extern pmd_t level2_fixmap_pgt[512];
  24 extern pmd_t level2_ident_pgt[512];
  25 extern pte_t level1_fixmap_pgt[512];
  26 extern pgd_t init_top_pgt[];
  27
  28 #define swapper_pg_dir init_top_pgt
  29
  30 extern void paging_init(void);
  31 static inline void sync_initial_page_table(void) { }
  32
  33 #define pte_ERROR(e)                                    \
  34         pr_err("%s:%d: bad pte %p(%016lx)\n",           \
  35                __FILE__, __LINE__, &(e), pte_val(e))
  36 #define pmd_ERROR(e)                                    \
  37         pr_err("%s:%d: bad pmd %p(%016lx)\n",           \
  38                __FILE__, __LINE__, &(e), pmd_val(e))
  39 #define pud_ERROR(e)                                    \
  40         pr_err("%s:%d: bad pud %p(%016lx)\n",           \
  41                __FILE__, __LINE__, &(e), pud_val(e))
  42
  43 #if CONFIG_PGTABLE_LEVELS >= 5
  44 #define p4d_ERROR(e)                                    \
  45         pr_err("%s:%d: bad p4d %p(%016lx)\n",           \
  46                __FILE__, __LINE__, &(e), p4d_val(e))
  47 #endif
  48
  49 #define pgd_ERROR(e)                                    \
  50         pr_err("%s:%d: bad pgd %p(%016lx)\n",           \
  51                __FILE__, __LINE__, &(e), pgd_val(e))
  52
  53 struct mm_struct;
  54
  55 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
  56 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
  57
  58 static inline void native_set_pte(pte_t *ptep, pte_t pte)
  59 {
  60         WRITE_ONCE(*ptep, pte);
  61 }
  62
  63 static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
  64                                     pte_t *ptep)
  65 {
  66         native_set_pte(ptep, native_make_pte(0));
  67 }
  68
  69 static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
  70 {
  71         native_set_pte(ptep, pte);
  72 }
  73
  74 static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
  75 {
  76         WRITE_ONCE(*pmdp, pmd);
  77 }
  78
  79 static inline void native_pmd_clear(pmd_t *pmd)
  80 {
  81         native_set_pmd(pmd, native_make_pmd(0));
  82 }
  83
  84 static inline pte_t native_ptep_get_and_clear(pte_t *xp)
  85 {
  86 #ifdef CONFIG_SMP
  87         return native_make_pte(xchg(&xp->pte, 0));
  88 #else
  89         /* native_local_ptep_get_and_clear,
  90            but duplicated because of cyclic dependency */
  91         pte_t ret = *xp;
  92         native_pte_clear(NULL, 0, xp);
  93         return ret;
  94 #endif
  95 }
  96
  97 static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
  98 {
  99 #ifdef CONFIG_SMP
 100         return native_make_pmd(xchg(&xp->pmd, 0));
 101 #else
 102         /* native_local_pmdp_get_and_clear,
 103            but duplicated because of cyclic dependency */
 104         pmd_t ret = *xp;
 105         native_pmd_clear(xp);
 106         return ret;
 107 #endif
 108 }
 109
 110 static inline void native_set_pud(pud_t *pudp, pud_t pud)
 111 {
 112         WRITE_ONCE(*pudp, pud);
 113 }
 114
 115 static inline void native_pud_clear(pud_t *pud)
 116 {
 117         native_set_pud(pud, native_make_pud(0));
 118 }
 119
 120 static inline pud_t native_pudp_get_and_clear(pud_t *xp)
 121 {
 122 #ifdef CONFIG_SMP
 123         return native_make_pud(xchg(&xp->pud, 0));
 124 #else
 125         /* native_local_pudp_get_and_clear,
 126          * but duplicated because of cyclic dependency
 127          */
 128         pud_t ret = *xp;
 129
 130         native_pud_clear(xp);
 131         return ret;
 132 #endif
 133 }
 134
 135 static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
 136 {
 137 #if defined(CONFIG_PAGE_TABLE_ISOLATION) && !defined(CONFIG_X86_5LEVEL)
 138         WRITE_ONCE(p4dp->pgd, pti_set_user_pgtbl(&p4dp->pgd, p4d.pgd));
 139 #else
 140         WRITE_ONCE(*p4dp, p4d);
 141 #endif
 142 }
 143
 144 static inline void native_p4d_clear(p4d_t *p4d)
 145 {
 146 #ifdef CONFIG_X86_5LEVEL
 147         native_set_p4d(p4d, native_make_p4d(0));
 148 #else
 149         native_set_p4d(p4d, (p4d_t) { .pgd = native_make_pgd(0)});
 150 #endif
 151 }
 152
 153 static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
 154 {
 155 #ifdef CONFIG_PAGE_TABLE_ISOLATION
 156         WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd));
 157 #else
 158         WRITE_ONCE(*pgdp, pgd);
 159 #endif
 160 }
 161
 162 static inline void native_pgd_clear(pgd_t *pgd)
 163 {
 164         native_set_pgd(pgd, native_make_pgd(0));
 165 }
 166
 167 extern void sync_global_pgds(unsigned long start, unsigned long end);
 168
 169 /*
 170  * Conversion functions: convert a page and protection to a page entry,
 171  * and a page entry and page directory to the page they refer to.
 172  */
 173
 174 /*
 175  * Level 4 access.
 176  */
 177 #define mk_kernel_pgd(address) __pgd((address) | _KERNPG_TABLE)
 178
 179 /* PUD - Level3 access */
 180
 181 /* PMD  - Level 2 access */
 182
 183 /* PTE - Level 1 access. */
 184
 185 /* x86-64 always has all page tables mapped. */
 186 #define pte_offset_map(dir, address) pte_offset_kernel((dir), (address))
 187 #define pte_unmap(pte) ((void)(pte))/* NOP */
 188
 189 /*
 190  * Encode and de-code a swap entry
 191  *
 192  * |     ...            | 11| 10|  9|8|7|6|5| 4| 3|2| 1|0| <- bit number
 193  * |     ...            |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names
 194  * | TYPE (59-63) | ~OFFSET (9-58)  |0|0|X|X| X| X|X|SD|0| <- swp entry
 195  *
 196  * G (8) is aliased and used as a PROT_NONE indicator for
 197  * !present ptes.  We need to start storing swap entries above
 198  * there.  We also need to avoid using A and D because of an
 199  * erratum where they can be incorrectly set by hardware on
 200  * non-present PTEs.
 201  *
 202  * SD (1) in swp entry is used to store soft dirty bit, which helps us
 203  * remember soft dirty over page migration
 204  *
 205  * Bit 7 in swp entry should be 0 because pmd_present checks not only P,
 206  * but also L and G.
 207  *
 208  * The offset is inverted by a binary not operation to make the high
 209  * physical bits set.
 210  */
 211 #define SWP_TYPE_BITS           5
 212
 213 #define SWP_OFFSET_FIRST_BIT    (_PAGE_BIT_PROTNONE + 1)
 214
 215 /* We always extract/encode the offset by shifting it all the way up, and then down again */
 216 #define SWP_OFFSET_SHIFT        (SWP_OFFSET_FIRST_BIT+SWP_TYPE_BITS)
 217
 218 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
 219
 220 /* Extract the high bits for type */
 221 #define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS))
 222
 223 /* Shift up (to get rid of type), then down to get value */
 224 #define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)
 225
 226 /*
 227  * Shift the offset up "too far" by TYPE bits, then down again
 228  * The offset is inverted by a binary not operation to make the high
 229  * physical bits set.
 230  */
 231 #define __swp_entry(type, offset) ((swp_entry_t) { \
 232         (~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
 233         | ((unsigned long)(type) << (64-SWP_TYPE_BITS)) })
 234
 235 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val((pte)) })
 236 #define __pmd_to_swp_entry(pmd)         ((swp_entry_t) { pmd_val((pmd)) })
 237 #define __swp_entry_to_pte(x)           ((pte_t) { .pte = (x).val })
 238 #define __swp_entry_to_pmd(x)           ((pmd_t) { .pmd = (x).val })
 239
 240 extern int kern_addr_valid(unsigned long addr);
 241 extern void cleanup_highmap(void);
 242
 243 #define HAVE_ARCH_UNMAPPED_AREA
 244 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 245
 246 #define pgtable_cache_init()   do { } while (0)
 247 #define check_pgt_cache()      do { } while (0)
 248
 249 #define PAGE_AGP    PAGE_KERNEL_NOCACHE
 250 #define HAVE_PAGE_AGP 1
 251
 252 /* fs/proc/kcore.c */
 253 #define kc_vaddr_to_offset(v) ((v) & __VIRTUAL_MASK)
 254 #define kc_offset_to_vaddr(o) ((o) | ~__VIRTUAL_MASK)
 255
 256 #define __HAVE_ARCH_PTE_SAME
 257
 258 #define vmemmap ((struct page *)VMEMMAP_START)
 259
 260 extern void init_extra_mapping_uc(unsigned long phys, unsigned long size);
 261 extern void init_extra_mapping_wb(unsigned long phys, unsigned long size);
 262
 263 #define gup_fast_permitted gup_fast_permitted
 264 static inline bool gup_fast_permitted(unsigned long start, int nr_pages,
 265                 int write)
 266 {
 267         unsigned long len, end;
 268
 269         len = (unsigned long)nr_pages << PAGE_SHIFT;
 270         end = start + len;
 271         if (end < start)
 272                 return false;
 273         if (end >> __VIRTUAL_MASK_SHIFT)
 274                 return false;
 275         return true;
 276 }
 277
 278 #include <asm/pgtable-invert.h>
 279
 280 #endif /* !__ASSEMBLY__ */
 281 #endif /* _ASM_X86_PGTABLE_64_H */