arch/powerpc/include/asm/book3s/64/pgalloc.h

   1 #ifndef _ASM_POWERPC_BOOK3S_64_PGALLOC_H
   2 #define _ASM_POWERPC_BOOK3S_64_PGALLOC_H
   3 /*
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9
  10 #include <linux/slab.h>
  11 #include <linux/cpumask.h>
  12 #include <linux/kmemleak.h>
  13 #include <linux/percpu.h>
  14
  15 struct vmemmap_backing {
  16         struct vmemmap_backing *list;
  17         unsigned long phys;
  18         unsigned long virt_addr;
  19 };
  20 extern struct vmemmap_backing *vmemmap_list;
  21
  22 /*
  23  * Functions that deal with pagetables that could be at any level of
  24  * the table need to be passed an "index_size" so they know how to
  25  * handle allocation.  For PTE pages (which are linked to a struct
  26  * page for now, and drawn from the main get_free_pages() pool), the
  27  * allocation size will be (2^index_size * sizeof(pointer)) and
  28  * allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
  29  *
  30  * The maximum index size needs to be big enough to allow any
  31  * pagetable sizes we need, but small enough to fit in the low bits of
  32  * any page table pointer.  In other words all pagetables, even tiny
  33  * ones, must be aligned to allow at least enough low 0 bits to
  34  * contain this value.  This value is also used as a mask, so it must
  35  * be one less than a power of two.
  36  */
  37 #define MAX_PGTABLE_INDEX_SIZE  0xf
  38
  39 extern struct kmem_cache *pgtable_cache[];
  40 #define PGT_CACHE(shift) pgtable_cache[shift]
  41
  42 extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int);
  43 extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
  44 extern void pte_fragment_free(unsigned long *, int);
  45 extern void pmd_fragment_free(unsigned long *);
  46 extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
  47 #ifdef CONFIG_SMP
  48 extern void __tlb_remove_table(void *_table);
  49 #endif
  50 void pte_frag_destroy(void *pte_frag);
  51
  52 static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
  53 {
  54 #ifdef CONFIG_PPC_64K_PAGES
  55         return (pgd_t *)__get_free_page(pgtable_gfp_flags(mm, PGALLOC_GFP));
  56 #else
  57         struct page *page;
  58         page = alloc_pages(pgtable_gfp_flags(mm, PGALLOC_GFP | __GFP_RETRY_MAYFAIL),
  59                                 4);
  60         if (!page)
  61                 return NULL;
  62         return (pgd_t *) page_address(page);
  63 #endif
  64 }
  65
  66 static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
  67 {
  68 #ifdef CONFIG_PPC_64K_PAGES
  69         free_page((unsigned long)pgd);
  70 #else
  71         free_pages((unsigned long)pgd, 4);
  72 #endif
  73 }
  74
  75 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  76 {
  77         pgd_t *pgd;
  78
  79         if (radix_enabled())
  80                 return radix__pgd_alloc(mm);
  81
  82         pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
  83                                pgtable_gfp_flags(mm, GFP_KERNEL));
  84         /*
  85          * Don't scan the PGD for pointers, it contains references to PUDs but
  86          * those references are not full pointers and so can't be recognised by
  87          * kmemleak.
  88          */
  89         kmemleak_no_scan(pgd);
  90
  91         /*
  92          * With hugetlb, we don't clear the second half of the page table.
  93          * If we share the same slab cache with the pmd or pud level table,
  94          * we need to make sure we zero out the full table on alloc.
  95          * With 4K we don't store slot in the second half. Hence we don't
  96          * need to do this for 4k.
  97          */
  98 #if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_PPC_64K_PAGES) && \
  99         (H_PGD_INDEX_SIZE == H_PUD_CACHE_INDEX)
 100         memset(pgd, 0, PGD_TABLE_SIZE);
 101 #endif
 102         return pgd;
 103 }
 104
 105 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 106 {
 107         if (radix_enabled())
 108                 return radix__pgd_free(mm, pgd);
 109         kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
 110 }
 111
 112 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 113 {
 114         pgd_set(pgd, __pgtable_ptr_val(pud) | PGD_VAL_BITS);
 115 }
 116
 117 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 118 {
 119         pud_t *pud;
 120
 121         pud = kmem_cache_alloc(PGT_CACHE(PUD_CACHE_INDEX),
 122                                pgtable_gfp_flags(mm, GFP_KERNEL));
 123         /*
 124          * Tell kmemleak to ignore the PUD, that means don't scan it for
 125          * pointers and don't consider it a leak. PUDs are typically only
 126          * referred to by their PGD, but kmemleak is not able to recognise those
 127          * as pointers, leading to false leak reports.
 128          */
 129         kmemleak_ignore(pud);
 130
 131         return pud;
 132 }
 133
 134 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 135 {
 136         kmem_cache_free(PGT_CACHE(PUD_CACHE_INDEX), pud);
 137 }
 138
 139 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 140 {
 141         pud_set(pud, __pgtable_ptr_val(pmd) | PUD_VAL_BITS);
 142 }
 143
 144 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
 145                                   unsigned long address)
 146 {
 147         /*
 148          * By now all the pud entries should be none entries. So go
 149          * ahead and flush the page walk cache
 150          */
 151         flush_tlb_pgtable(tlb, address);
 152         pgtable_free_tlb(tlb, pud, PUD_INDEX);
 153 }
 154
 155 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 156 {
 157         return pmd_fragment_alloc(mm, addr);
 158 }
 159
 160 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 161 {
 162         pmd_fragment_free((unsigned long *)pmd);
 163 }
 164
 165 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
 166                                   unsigned long address)
 167 {
 168         /*
 169          * By now all the pud entries should be none entries. So go
 170          * ahead and flush the page walk cache
 171          */
 172         flush_tlb_pgtable(tlb, address);
 173         return pgtable_free_tlb(tlb, pmd, PMD_INDEX);
 174 }
 175
 176 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
 177                                        pte_t *pte)
 178 {
 179         pmd_set(pmd, __pgtable_ptr_val(pte) | PMD_VAL_BITS);
 180 }
 181
 182 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 183                                 pgtable_t pte_page)
 184 {
 185         pmd_set(pmd, __pgtable_ptr_val(pte_page) | PMD_VAL_BITS);
 186 }
 187
 188 static inline pgtable_t pmd_pgtable(pmd_t pmd)
 189 {
 190         return (pgtable_t)pmd_page_vaddr(pmd);
 191 }
 192
 193 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
 194                                           unsigned long address)
 195 {
 196         return (pte_t *)pte_fragment_alloc(mm, address, 1);
 197 }
 198
 199 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
 200                                       unsigned long address)
 201 {
 202         return (pgtable_t)pte_fragment_alloc(mm, address, 0);
 203 }
 204
 205 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
 206 {
 207         pte_fragment_free((unsigned long *)pte, 1);
 208 }
 209
 210 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
 211 {
 212         pte_fragment_free((unsigned long *)ptepage, 0);
 213 }
 214
 215 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
 216                                   unsigned long address)
 217 {
 218         /*
 219          * By now all the pud entries should be none entries. So go
 220          * ahead and flush the page walk cache
 221          */
 222         flush_tlb_pgtable(tlb, address);
 223         pgtable_free_tlb(tlb, table, PTE_INDEX);
 224 }
 225
 226 #define check_pgt_cache()       do { } while (0)
 227
 228 extern atomic_long_t direct_pages_count[MMU_PAGE_COUNT];
 229 static inline void update_page_count(int psize, long count)
 230 {
 231         if (IS_ENABLED(CONFIG_PROC_FS))
 232                 atomic_long_add(count, &direct_pages_count[psize]);
 233 }
 234
 235 #endif /* _ASM_POWERPC_BOOK3S_64_PGALLOC_H */