Line data    Source code

       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             : #define mm_p4d_folded mm_p4d_folded
      57             : static inline bool mm_p4d_folded(struct mm_struct *mm)
      58             : {
      59             :         return !pgtable_l5_enabled();
      60             : }
      61             : 
      62             : void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
      63             : void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
      64             : 
      65             : static inline void native_set_pte(pte_t *ptep, pte_t pte)
      66             : {
      67             :         WRITE_ONCE(*ptep, pte);
      68             : }
      69             : 
      70             : static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
      71             :                                     pte_t *ptep)
      72             : {
      73             :         native_set_pte(ptep, native_make_pte(0));
      74             : }
      75             : 
      76             : static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
      77             : {
      78             :         native_set_pte(ptep, pte);
      79             : }
      80             : 
      81             : static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
      82             : {
      83           0 :         WRITE_ONCE(*pmdp, pmd);
      84             : }
      85             : 
      86             : static inline void native_pmd_clear(pmd_t *pmd)
      87             : {
      88             :         native_set_pmd(pmd, native_make_pmd(0));
      89             : }
      90             : 
      91             : static inline pte_t native_ptep_get_and_clear(pte_t *xp)
      92             : {
      93             : #ifdef CONFIG_SMP
      94             :         return native_make_pte(xchg(&xp->pte, 0));
      95             : #else
      96             :         /* native_local_ptep_get_and_clear,
      97             :            but duplicated because of cyclic dependency */
      98             :         pte_t ret = *xp;
      99             :         native_pte_clear(NULL, 0, xp);
     100             :         return ret;
     101             : #endif
     102             : }
     103             : 
     104             : static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
     105             : {
     106             : #ifdef CONFIG_SMP
     107             :         return native_make_pmd(xchg(&xp->pmd, 0));
     108             : #else
     109             :         /* native_local_pmdp_get_and_clear,
     110             :            but duplicated because of cyclic dependency */
     111             :         pmd_t ret = *xp;
     112             :         native_pmd_clear(xp);
     113             :         return ret;
     114             : #endif
     115             : }
     116             : 
     117             : static inline void native_set_pud(pud_t *pudp, pud_t pud)
     118             : {
     119             :         WRITE_ONCE(*pudp, pud);
     120             : }
     121             : 
     122             : static inline void native_pud_clear(pud_t *pud)
     123             : {
     124             :         native_set_pud(pud, native_make_pud(0));
     125             : }
     126             : 
     127             : static inline pud_t native_pudp_get_and_clear(pud_t *xp)
     128             : {
     129             : #ifdef CONFIG_SMP
     130             :         return native_make_pud(xchg(&xp->pud, 0));
     131             : #else
     132             :         /* native_local_pudp_get_and_clear,
     133             :          * but duplicated because of cyclic dependency
     134             :          */
     135             :         pud_t ret = *xp;
     136             : 
     137             :         native_pud_clear(xp);
     138             :         return ret;
     139             : #endif
     140             : }
     141             : 
     142             : static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
     143             : {
     144             :         pgd_t pgd;
     145             : 
     146             :         if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
     147             :                 WRITE_ONCE(*p4dp, p4d);
     148             :                 return;
     149             :         }
     150             : 
     151             :         pgd = native_make_pgd(native_p4d_val(p4d));
     152             :         pgd = pti_set_user_pgtbl((pgd_t *)p4dp, pgd);
     153             :         WRITE_ONCE(*p4dp, native_make_p4d(native_pgd_val(pgd)));
     154             : }
     155             : 
     156             : static inline void native_p4d_clear(p4d_t *p4d)
     157             : {
     158             :         native_set_p4d(p4d, native_make_p4d(0));
     159             : }
     160             : 
     161             : static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
     162             : {
     163             :         WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd));
     164             : }
     165             : 
     166             : static inline void native_pgd_clear(pgd_t *pgd)
     167             : {
     168             :         native_set_pgd(pgd, native_make_pgd(0));
     169             : }
     170             : 
     171             : /*
     172             :  * Conversion functions: convert a page and protection to a page entry,
     173             :  * and a page entry and page directory to the page they refer to.
     174             :  */
     175             : 
     176             : /* PGD - Level 4 access */
     177             : 
     178             : /* PUD - Level 3 access */
     179             : 
     180             : /* PMD - Level 2 access */
     181             : 
     182             : /* PTE - Level 1 access */
     183             : 
     184             : /*
     185             :  * Encode and de-code a swap entry
     186             :  *
     187             :  * |     ...            | 11| 10|  9|8|7|6|5| 4| 3|2| 1|0| <- bit number
     188             :  * |     ...            |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names
     189             :  * | TYPE (59-63) | ~OFFSET (9-58)  |0|0|X|X| X| E|F|SD|0| <- swp entry
     190             :  *
     191             :  * G (8) is aliased and used as a PROT_NONE indicator for
     192             :  * !present ptes.  We need to start storing swap entries above
     193             :  * there.  We also need to avoid using A and D because of an
     194             :  * erratum where they can be incorrectly set by hardware on
     195             :  * non-present PTEs.
     196             :  *
     197             :  * SD Bits 1-4 are not used in non-present format and available for
     198             :  * special use described below:
     199             :  *
     200             :  * SD (1) in swp entry is used to store soft dirty bit, which helps us
     201             :  * remember soft dirty over page migration
     202             :  *
     203             :  * F (2) in swp entry is used to record when a pagetable is
     204             :  * writeprotected by userfaultfd WP support.
     205             :  *
     206             :  * E (3) in swp entry is used to rememeber PG_anon_exclusive.
     207             :  *
     208             :  * Bit 7 in swp entry should be 0 because pmd_present checks not only P,
     209             :  * but also L and G.
     210             :  *
     211             :  * The offset is inverted by a binary not operation to make the high
     212             :  * physical bits set.
     213             :  */
     214             : #define SWP_TYPE_BITS           5
     215             : 
     216             : #define SWP_OFFSET_FIRST_BIT    (_PAGE_BIT_PROTNONE + 1)
     217             : 
     218             : /* We always extract/encode the offset by shifting it all the way up, and then down again */
     219             : #define SWP_OFFSET_SHIFT        (SWP_OFFSET_FIRST_BIT+SWP_TYPE_BITS)
     220             : 
     221             : #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
     222             : 
     223             : /* Extract the high bits for type */
     224             : #define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS))
     225             : 
     226             : /* Shift up (to get rid of type), then down to get value */
     227             : #define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)
     228             : 
     229             : /*
     230             :  * Shift the offset up "too far" by TYPE bits, then down again
     231             :  * The offset is inverted by a binary not operation to make the high
     232             :  * physical bits set.
     233             :  */
     234             : #define __swp_entry(type, offset) ((swp_entry_t) { \
     235             :         (~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
     236             :         | ((unsigned long)(type) << (64-SWP_TYPE_BITS)) })
     237             : 
     238             : #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val((pte)) })
     239             : #define __pmd_to_swp_entry(pmd)         ((swp_entry_t) { pmd_val((pmd)) })
     240             : #define __swp_entry_to_pte(x)           (__pte((x).val))
     241             : #define __swp_entry_to_pmd(x)           (__pmd((x).val))
     242             : 
     243             : extern void cleanup_highmap(void);
     244             : 
     245             : #define HAVE_ARCH_UNMAPPED_AREA
     246             : #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
     247             : 
     248             : #define PAGE_AGP    PAGE_KERNEL_NOCACHE
     249             : #define HAVE_PAGE_AGP 1
     250             : 
     251             : /* fs/proc/kcore.c */
     252             : #define kc_vaddr_to_offset(v) ((v) & __VIRTUAL_MASK)
     253             : #define kc_offset_to_vaddr(o) ((o) | ~__VIRTUAL_MASK)
     254             : 
     255             : #define __HAVE_ARCH_PTE_SAME
     256             : 
     257             : #define vmemmap ((struct page *)VMEMMAP_START)
     258             : 
     259             : extern void init_extra_mapping_uc(unsigned long phys, unsigned long size);
     260             : extern void init_extra_mapping_wb(unsigned long phys, unsigned long size);
     261             : 
     262             : #define gup_fast_permitted gup_fast_permitted
     263             : static inline bool gup_fast_permitted(unsigned long start, unsigned long end)
     264             : {
     265             :         if (end >> __VIRTUAL_MASK_SHIFT)
     266             :                 return false;
     267             :         return true;
     268             : }
     269             : 
     270             : #include <asm/pgtable-invert.h>
     271             : 
     272             : #endif /* !__ASSEMBLY__ */
     273             : #endif /* _ASM_X86_PGTABLE_64_H */