arch/powerpc/include/asm/book3s/32/pgalloc.h

   1 #ifndef _ASM_POWERPC_BOOK3S_32_PGALLOC_H
   2 #define _ASM_POWERPC_BOOK3S_32_PGALLOC_H
   3
   4 #include <linux/threads.h>
   5 #include <linux/slab.h>
   6
   7 /*
   8  * Functions that deal with pagetables that could be at any level of
   9  * the table need to be passed an "index_size" so they know how to
  10  * handle allocation.  For PTE pages (which are linked to a struct
  11  * page for now, and drawn from the main get_free_pages() pool), the
  12  * allocation size will be (2^index_size * sizeof(pointer)) and
  13  * allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
  14  *
  15  * The maximum index size needs to be big enough to allow any
  16  * pagetable sizes we need, but small enough to fit in the low bits of
  17  * any page table pointer.  In other words all pagetables, even tiny
  18  * ones, must be aligned to allow at least enough low 0 bits to
  19  * contain this value.  This value is also used as a mask, so it must
  20  * be one less than a power of two.
  21  */
  22 #define MAX_PGTABLE_INDEX_SIZE  0xf
  23
  24 extern void __bad_pte(pmd_t *pmd);
  25
  26 extern struct kmem_cache *pgtable_cache[];
  27 #define PGT_CACHE(shift) ({                             \
  28                         BUG_ON(!(shift));               \
  29                         pgtable_cache[(shift) - 1];     \
  30                 })
  31
  32 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  33 {
  34         return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
  35                         pgtable_gfp_flags(mm, GFP_KERNEL));
  36 }
  37
  38 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  39 {
  40         kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
  41 }
  42
  43 /*
  44  * We don't have any real pmd's, and this code never triggers because
  45  * the pgd will always be present..
  46  */
  47 /* #define pmd_alloc_one(mm,address)       ({ BUG(); ((pmd_t *)2); }) */
  48 #define pmd_free(mm, x)                 do { } while (0)
  49 #define __pmd_free_tlb(tlb,x,a)         do { } while (0)
  50 /* #define pgd_populate(mm, pmd, pte)      BUG() */
  51
  52 #ifndef CONFIG_BOOKE
  53
  54 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  55                                        pte_t *pte)
  56 {
  57         *pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
  58 }
  59
  60 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  61                                 pgtable_t pte_page)
  62 {
  63         *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_PRESENT);
  64 }
  65
  66 #define pmd_pgtable(pmd) pmd_page(pmd)
  67 #else
  68
  69 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  70                                        pte_t *pte)
  71 {
  72         *pmdp = __pmd((unsigned long)pte | _PMD_PRESENT);
  73 }
  74
  75 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  76                                 pgtable_t pte_page)
  77 {
  78         *pmdp = __pmd((unsigned long)lowmem_page_address(pte_page) | _PMD_PRESENT);
  79 }
  80
  81 #define pmd_pgtable(pmd) pmd_page(pmd)
  82 #endif
  83
  84 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
  85 extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
  86
  87 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  88 {
  89         free_page((unsigned long)pte);
  90 }
  91
  92 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
  93 {
  94         pgtable_page_dtor(ptepage);
  95         __free_page(ptepage);
  96 }
  97
  98 static inline void pgtable_free(void *table, unsigned index_size)
  99 {
 100         if (!index_size) {
 101                 free_page((unsigned long)table);
 102         } else {
 103                 BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
 104                 kmem_cache_free(PGT_CACHE(index_size), table);
 105         }
 106 }
 107
 108 #define check_pgt_cache()       do { } while (0)
 109
 110 #ifdef CONFIG_SMP
 111 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 112                                     void *table, int shift)
 113 {
 114         unsigned long pgf = (unsigned long)table;
 115         BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
 116         pgf |= shift;
 117         tlb_remove_table(tlb, (void *)pgf);
 118 }
 119
 120 static inline void __tlb_remove_table(void *_table)
 121 {
 122         void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
 123         unsigned shift = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
 124
 125         pgtable_free(table, shift);
 126 }
 127 #else
 128 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 129                                     void *table, int shift)
 130 {
 131         pgtable_free(table, shift);
 132 }
 133 #endif
 134
 135 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
 136                                   unsigned long address)
 137 {
 138         pgtable_page_dtor(table);
 139         pgtable_free_tlb(tlb, page_address(table), 0);
 140 }
 141 #endif /* _ASM_POWERPC_BOOK3S_32_PGALLOC_H */