1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_PGALLOC_32_H
3 #define _ASM_POWERPC_PGALLOC_32_H
5 #include <linux/threads.h>
6 #include <linux/slab.h>
9 * Functions that deal with pagetables that could be at any level of
10 * the table need to be passed an "index_size" so they know how to
11 * handle allocation. For PTE pages (which are linked to a struct
12 * page for now, and drawn from the main get_free_pages() pool), the
13 * allocation size will be (2^index_size * sizeof(pointer)) and
14 * allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
16 * The maximum index size needs to be big enough to allow any
17 * pagetable sizes we need, but small enough to fit in the low bits of
18 * any page table pointer. In other words all pagetables, even tiny
19 * ones, must be aligned to allow at least enough low 0 bits to
20 * contain this value. This value is also used as a mask, so it must
21 * be one less than a power of two.
23 #define MAX_PGTABLE_INDEX_SIZE 0xf
25 extern void __bad_pte(pmd_t *pmd);
27 extern struct kmem_cache *pgtable_cache[];
28 #define PGT_CACHE(shift) ({ \
30 pgtable_cache[(shift) - 1]; \
33 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
35 return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
36 pgtable_gfp_flags(mm, GFP_KERNEL));
39 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
41 kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
45 * We don't have any real pmd's, and this code never triggers because
46 * the pgd will always be present..
48 /* #define pmd_alloc_one(mm,address) ({ BUG(); ((pmd_t *)2); }) */
49 #define pmd_free(mm, x) do { } while (0)
50 #define __pmd_free_tlb(tlb,x,a) do { } while (0)
51 /* #define pgd_populate(mm, pmd, pte) BUG() */
55 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
58 *pmdp = __pmd(__pa(pte) | _PMD_PRESENT);
61 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
64 *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_USER |
68 #define pmd_pgtable(pmd) pmd_page(pmd)
71 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
74 *pmdp = __pmd((unsigned long)pte | _PMD_PRESENT);
77 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
80 *pmdp = __pmd((unsigned long)lowmem_page_address(pte_page) | _PMD_PRESENT);
83 #define pmd_pgtable(pmd) pmd_page(pmd)
86 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
87 extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
89 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
91 free_page((unsigned long)pte);
94 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
96 pgtable_page_dtor(ptepage);
100 static inline void pgtable_free(void *table, unsigned index_size)
103 pgtable_page_dtor(virt_to_page(table));
104 free_page((unsigned long)table);
106 BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
107 kmem_cache_free(PGT_CACHE(index_size), table);
111 #define check_pgt_cache() do { } while (0)
112 #define get_hugepd_cache_index(x) (x)
115 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
116 void *table, int shift)
118 unsigned long pgf = (unsigned long)table;
119 BUG_ON(shift > MAX_PGTABLE_INDEX_SIZE);
121 tlb_remove_table(tlb, (void *)pgf);
124 static inline void __tlb_remove_table(void *_table)
126 void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
127 unsigned shift = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
129 pgtable_free(table, shift);
132 static inline void pgtable_free_tlb(struct mmu_gather *tlb,
133 void *table, int shift)
135 pgtable_free(table, shift);
139 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
140 unsigned long address)
142 tlb_flush_pgtable(tlb, address);
143 pgtable_free_tlb(tlb, page_address(table), 0);
145 #endif /* _ASM_POWERPC_PGALLOC_32_H */