LXR linux/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
  24extern void __bad_pte(pmd_t *pmd);
  25
  26extern struct kmem_cache *pgtable_cache[];
  27#define PGT_CACHE(shift) ({                             \
  28                        BUG_ON(!(shift));               \
  29                        pgtable_cache[(shift) - 1];     \
  30                })
  31
  32static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  33{
  34        return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), GFP_KERNEL);
  35}
  36
  37static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
  38{
  39        kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
  40}
  41
  42/*
  43 * We don't have any real pmd's, and this code never triggers because
  44 * the pgd will always be present..
  45 */
  46/* #define pmd_alloc_one(mm,address)       ({ BUG(); ((pmd_t *)2); }) */
  47#define pmd_free(mm, x)                 do { } while (0)
  48#define __pmd_free_tlb(tlb,x,a)         do { } while (0)
  49/* #define pgd_populate(mm, pmd, pte)      BUG() */
  50
  51#ifndef CONFIG_BOOKE
  52
  53static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  54                                       pte_t *pte)
  55{
  56        *pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
  57}
  58
  59static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  60                                pgtable_t pte_page)
  61{
  62        *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_PRESENT);
  63}
  64
  65#define pmd_pgtable(pmd) pmd_page(pmd)
  66#else
  67
  68static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
  69                                       pte_t *pte)
  70{
  71        *pmdp = __pmd((unsigned long)pte | _PMD_PRESENT);
  72}
  73
  74static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
  75                                pgtable_t pte_page)
  76{
  77        *pmdp = __pmd((unsigned long)lowmem_page_address(pte_page) | _PMD_PRESENT);
  78}
  79
  80#define pmd_pgtable(pmd) pmd_page(pmd)
  81#endif
  82
  83extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
  84extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
  85
  86static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  87{
  88        free_page((unsigned long)pte);
  89}
  90
  91static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
  92{
  93        pgtable_page_dtor(ptepage);
  94        __free_page(ptepage);
  95}
  96
  97static inline void pgtable_free(void *table, unsigned index_size)
  98{
  99        if (!index_size) {
 100                free_page((unsigned long)table);
 101        } else {
 102                BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
 103                kmem_cache_free(PGT_CACHE(index_size), table);
 104        }
 105}
 106
 107#define check_pgt_cache()       do { } while (0)
 108
 109#ifdef CONFIG_SMP
 110static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 111                                    void *table, int shift)
 112{
 113        unsigned long pgf = (unsigned long)table;
 114        BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
 115        pgf |= shift;
 116        tlb_remove_table(tlb, (void *)pgf);
 117}
 118
 119static inline void __tlb_remove_table(void *_table)
 120{
 121        void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
 122        unsigned shift = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
 123
 124        pgtable_free(table, shift);
 125}
 126#else
 127static inline void pgtable_free_tlb(struct mmu_gather *tlb,
 128                                    void *table, int shift)
 129{
 130        pgtable_free(table, shift);
 131}
 132#endif
 133
 134static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
 135                                  unsigned long address)
 136{
 137        pgtable_page_dtor(table);
 138        pgtable_free_tlb(tlb, page_address(table), 0);
 139}
 140#endif /* _ASM_POWERPC_BOOK3S_32_PGALLOC_H */
 141