1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/mm.h> 3 #include <linux/slab.h> 4 5 static struct kmem_cache *pgd_cachep; 6 #if PAGETABLE_LEVELS > 2 7 static struct kmem_cache *pmd_cachep; 8 #endif 9 10 void pgd_ctor(void *x) 11 { 12 pgd_t *pgd = x; 13 14 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t)); 15 memcpy(pgd + USER_PTRS_PER_PGD, 16 swapper_pg_dir + USER_PTRS_PER_PGD, 17 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t)); 18 } 19 20 void pgtable_cache_init(void) 21 { 22 pgd_cachep = kmem_cache_create("pgd_cache", 23 PTRS_PER_PGD * (1<<PTE_MAGNITUDE), 24 PAGE_SIZE, SLAB_PANIC, pgd_ctor); 25 #if PAGETABLE_LEVELS > 2 26 pmd_cachep = kmem_cache_create("pmd_cache", 27 PTRS_PER_PMD * (1<<PTE_MAGNITUDE), 28 PAGE_SIZE, SLAB_PANIC, NULL); 29 #endif 30 } 31 32 pgd_t *pgd_alloc(struct mm_struct *mm) 33 { 34 return kmem_cache_alloc(pgd_cachep, GFP_KERNEL); 35 } 36 37 void pgd_free(struct mm_struct *mm, pgd_t *pgd) 38 { 39 kmem_cache_free(pgd_cachep, pgd); 40 } 41 42 #if PAGETABLE_LEVELS > 2 43 void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) 44 { 45 set_pud(pud, __pud((unsigned long)pmd)); 46 } 47 48 pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) 49 { 50 return kmem_cache_alloc(pmd_cachep, GFP_KERNEL | __GFP_ZERO); 51 } 52 53 void pmd_free(struct mm_struct *mm, pmd_t *pmd) 54 { 55 kmem_cache_free(pmd_cachep, pmd); 56 } 57 #endif /* PAGETABLE_LEVELS > 2 */ 58