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