arch/x86/include/asm/pgalloc.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_PGALLOC_H
   3 #define _ASM_X86_PGALLOC_H
   4
   5 #include <linux/threads.h>
   6 #include <linux/mm.h>           /* for struct page */
   7 #include <linux/pagemap.h>
   8
   9 #define __HAVE_ARCH_PTE_ALLOC_ONE
  10 #include <asm-generic/pgalloc.h>        /* for pte_{alloc,free}_one */
  11
  12 static inline int  __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }
  13
  14 #ifdef CONFIG_PARAVIRT_XXL
  15 #include <asm/paravirt.h>
  16 #else
  17 #define paravirt_pgd_alloc(mm)  __paravirt_pgd_alloc(mm)
  18 static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
  19 static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)  {}
  20 static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)  {}
  21 static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,
  22                                             unsigned long start, unsigned long count) {}
  23 static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)  {}
  24 static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)  {}
  25 static inline void paravirt_release_pte(unsigned long pfn) {}
  26 static inline void paravirt_release_pmd(unsigned long pfn) {}
  27 static inline void paravirt_release_pud(unsigned long pfn) {}
  28 static inline void paravirt_release_p4d(unsigned long pfn) {}
  29 #endif
  30
  31 /*
  32  * Flags to use when allocating a user page table page.
  33  */
  34 extern gfp_t __userpte_alloc_gfp;
  35
  36 #ifdef CONFIG_PAGE_TABLE_ISOLATION
  37 /*
  38  * Instead of one PGD, we acquire two PGDs.  Being order-1, it is
  39  * both 8k in size and 8k-aligned.  That lets us just flip bit 12
  40  * in a pointer to swap between the two 4k halves.
  41  */
  42 #define PGD_ALLOCATION_ORDER 1
  43 #else
  44 #define PGD_ALLOCATION_ORDER 0
  45 #endif
  46
  47 /*
  48  * Allocate and free page tables.
  49  */
  50 extern pgd_t *pgd_alloc(struct mm_struct *);
  51 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
  52
  53 extern pgtable_t pte_alloc_one(struct mm_struct *);
  54
  55 extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
  56
  57 static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
  58                                   unsigned long address)
  59 {
  60         ___pte_free_tlb(tlb, pte);
  61 }
  62
  63 static inline void pmd_populate_kernel(struct mm_struct *mm,
  64                                        pmd_t *pmd, pte_t *pte)
  65 {
  66         paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
  67         set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
  68 }
  69
  70 static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
  71                                        pmd_t *pmd, pte_t *pte)
  72 {
  73         paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
  74         set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
  75 }
  76
  77 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
  78                                 struct page *pte)
  79 {
  80         unsigned long pfn = page_to_pfn(pte);
  81
  82         paravirt_alloc_pte(mm, pfn);
  83         set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
  84 }
  85
  86 #define pmd_pgtable(pmd) pmd_page(pmd)
  87
  88 #if CONFIG_PGTABLE_LEVELS > 2
  89 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
  90 {
  91         struct page *page;
  92         gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO;
  93
  94         if (mm == &init_mm)
  95                 gfp &= ~__GFP_ACCOUNT;
  96         page = alloc_pages(gfp, 0);
  97         if (!page)
  98                 return NULL;
  99         if (!pgtable_pmd_page_ctor(page)) {
 100                 __free_pages(page, 0);
 101                 return NULL;
 102         }
 103         return (pmd_t *)page_address(page);
 104 }
 105
 106 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 107 {
 108         BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
 109         pgtable_pmd_page_dtor(virt_to_page(pmd));
 110         free_page((unsigned long)pmd);
 111 }
 112
 113 extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
 114
 115 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
 116                                   unsigned long address)
 117 {
 118         ___pmd_free_tlb(tlb, pmd);
 119 }
 120
 121 #ifdef CONFIG_X86_PAE
 122 extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
 123 #else   /* !CONFIG_X86_PAE */
 124 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 125 {
 126         paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
 127         set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
 128 }
 129
 130 static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 131 {
 132         paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
 133         set_pud_safe(pud, __pud(_PAGE_TABLE | __pa(pmd)));
 134 }
 135 #endif  /* CONFIG_X86_PAE */
 136
 137 #if CONFIG_PGTABLE_LEVELS > 3
 138 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 139 {
 140         paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
 141         set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
 142 }
 143
 144 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 145 {
 146         paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
 147         set_p4d_safe(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
 148 }
 149
 150 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 151 {
 152         gfp_t gfp = GFP_KERNEL_ACCOUNT;
 153
 154         if (mm == &init_mm)
 155                 gfp &= ~__GFP_ACCOUNT;
 156         return (pud_t *)get_zeroed_page(gfp);
 157 }
 158
 159 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 160 {
 161         BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
 162         free_page((unsigned long)pud);
 163 }
 164
 165 extern void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud);
 166
 167 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
 168                                   unsigned long address)
 169 {
 170         ___pud_free_tlb(tlb, pud);
 171 }
 172
 173 #if CONFIG_PGTABLE_LEVELS > 4
 174 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 175 {
 176         if (!pgtable_l5_enabled())
 177                 return;
 178         paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
 179         set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
 180 }
 181
 182 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 183 {
 184         if (!pgtable_l5_enabled())
 185                 return;
 186         paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
 187         set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
 188 }
 189
 190 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
 191 {
 192         gfp_t gfp = GFP_KERNEL_ACCOUNT;
 193
 194         if (mm == &init_mm)
 195                 gfp &= ~__GFP_ACCOUNT;
 196         return (p4d_t *)get_zeroed_page(gfp);
 197 }
 198
 199 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
 200 {
 201         if (!pgtable_l5_enabled())
 202                 return;
 203
 204         BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
 205         free_page((unsigned long)p4d);
 206 }
 207
 208 extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
 209
 210 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
 211                                   unsigned long address)
 212 {
 213         if (pgtable_l5_enabled())
 214                 ___p4d_free_tlb(tlb, p4d);
 215 }
 216
 217 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
 218 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
 219 #endif  /* CONFIG_PGTABLE_LEVELS > 2 */
 220
 221 #endif /* _ASM_X86_PGALLOC_H */